USAP-DC

{"dp_type": "Project", "free_text": "Diatom"}

[{"awards": "2207011 Granger, Julie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 04 Mar 2024 00:00:00 GMT", "description": "Iron is a limiting nutrient for primary production in 30% of the global ocean, including the Southern Ocean. Dinoflagellates thrive in a wide variety of coastal and oceanic environments, including iron-limited regions. As iron is a biologically essential element for the growth and proliferation of marine algae, dinoflagellates may have evolved strategic mechanisms to combat iron limitation. Presently, these mechanisms have been scantly investigated in dinoflagellates. Here, we compare the growth response of the well-studied diatom Thalasiossira weissflogii to that of dinoflagellates Amphidinium carterae, Heterocapsa triquetra, and Symbiodinium tridacnidorum to different iron conditions: (a) iron-replete medium, (b) iron-limited medium, and (c) iron-limited medium supplemented with the siderophore Deferoxamine B (DFB). Preliminary observations suggest that A. carterae is able to assimilate iron bound to DFB, in contrast to T. weissflogii and Heterocapsa triquetra. A survey of the transcriptome of A. carterae suggests that it possess genes analogous to the TonB-dependent receptors (TBDRs) associated with iron-siderophore transport in prokaryotes. Additional species of dinoflagellates will be observed to investigate the ubiquity of this strategy in dinoflagellates. A more comprehensive understanding of dinoflagellate acclimation to low iron conditions is key to understanding their ecophysiology and the biogeochemical dynamics of iron-limited regions.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Dinoflagellates; Iron; United States Of America; Iron Acquisition; Siderophore; TRACE ELEMENTS; Iron Limitation", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Granger, Julie; Lin, Senjie", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Siderophore utilization by dinoflagellates as a strategy for iron acquisition", "uid": "p0010455", "west": -180.0}, {"awards": "1939139 Scherer, Reed", "bounds_geometry": "POLYGON((-120 -66,-117.5 -66,-115 -66,-112.5 -66,-110 -66,-107.5 -66,-105 -66,-102.5 -66,-100 -66,-97.5 -66,-95 -66,-95 -67.1,-95 -68.2,-95 -69.3,-95 -70.4,-95 -71.5,-95 -72.6,-95 -73.7,-95 -74.8,-95 -75.9,-95 -77,-97.5 -77,-100 -77,-102.5 -77,-105 -77,-107.5 -77,-110 -77,-112.5 -77,-115 -77,-117.5 -77,-120 -77,-120 -75.9,-120 -74.8,-120 -73.7,-120 -72.6,-120 -71.5,-120 -70.4,-120 -69.3,-120 -68.2,-120 -67.1,-120 -66))", "dataset_titles": "Last Interglacial Southern Ocean paleothermometry from diatom morphometrics: Analysis and application of the F. kerguelensis Valve Rectangularity Sea Surface Temperature proxy.; Pliocene diatom abundance, IODP 397-U1532", "datasets": [{"dataset_uid": "601769", "doi": null, "keywords": "Antarctica; Biogenic Silica; Diatom", "people": "Scherer, Reed Paul", "repository": "USAP-DC", "science_program": null, "title": "Pliocene diatom abundance, IODP 397-U1532", "url": "https://www.usap-dc.org/view/dataset/601769"}, {"dataset_uid": "601767", "doi": null, "keywords": "Amundsen Sea; Antarctica; Sabrina Coast; Southern Ocean", "people": "Ruggiero, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Last Interglacial Southern Ocean paleothermometry from diatom morphometrics: Analysis and application of the F. kerguelensis Valve Rectangularity Sea Surface Temperature proxy.", "url": "https://www.usap-dc.org/view/dataset/601767"}], "date_created": "Tue, 20 Feb 2024 00:00:00 GMT", "description": "Part I, Non-technical Abstract \u003cbr/\u003eConcerns that the West Antarctic Ice Sheet (WAIS) might be susceptible to releasing its ice as giant icebergs into the Southern Ocean due to a warming climate, raising global sea level, were first expressed more than 40 years ago. To best-assess this threat, scientists need to know whether such events occurred in the geologically recent past, during warm intervals of past glacial-interglacial cycles. Ocean drilling near the most vulnerable sector of the WAIS, in 2019, yielded seafloor geologic records demonstrating times when icebergs dropped large volumes of sands and pebbles, called ice-rafted detritus (IRD) in deep water of the Amundsen Sea. Occurring together with IRD that was eroded from bedrock beneath the ice sheets, there are abundant microfossils of diatoms (algal plankton), which indicate high biological productivity in the open ocean. The new sediment cores provide a complete, uninterrupted record of a time of dramatic fluctuations of ice sheet extent that occurred over the last 3 million years. Therefore, they provide the means to obtain clear answers to the question whether ice sheet collapse occurred in the past and offering clues to its potential future. This project will investigate sediment intervals where IRD coincides with evidence of high diatom production, to test whether these two criteria indicate rapid ice sheet collapse. Geochemical analysis of IRD pebbles will help trace the source of the icebergs to likely on-land sites. By analyzing conditions of high diatom and IRD accumulation in deep ocean sediment, where local coastal influences can be avoided, we will assess oceanographic and climatic conditions associated with past ice sheet collapse events. Diatoms provide powerful evidence of temperature and ocean productivity changes in the past, that, when linked to time, can translate into rates of ice sheet drawdown. These results will provide critical data for designing, constraining and testing the next suite computer models that can determine the likelihood and timing of future ice sheet collapse in a warming world. The project will include training of undergraduate and graduate students from diverse backgrounds, and the public will be introduced to Antarctic science and engaged through several different outreach efforts.\u003cbr/\u003e\u003cbr/\u003ePart 2, Technical Abstract\u003cbr/\u003e\u003cbr/\u003eNew drillcores from the Amundsen Sea, Antarctica (IODP Expedition 379) contain a continuous record of oceanographic changes and iceberg rafted debris (IRD) spanning the last 5 million years. This study aims to identify the signature of retreat/collapse of the West Antarctic Ice Sheet (WAIS) in these continental margin, deep-sea sediments by quantitatively analyzing, in detail, diatom and IRD records across glacial-interglacial lithostratigraphic transitions to establish the timing and frequency of Late Pliocene and Pleistocene WAIS collapse events. The investigators will secure age constraints and diagnostic observations of marine paleoenvironmental conditions for selected interglacial intervals of cores from sites U1532 and U1533, using high resolution micropaleontology of diatom assemblages coupled with microstratigraphic analysis of IRD depositional events, while petrography, geochronology and thermochronology of iceberg rafted clasts will provide evidence of iceberg sources and pathways. Depositional paleotemperatures will be assessed via a new paleotemperature proxy based on quantitative assessment of morphologic changes in the dominant Southern Ocean diatom Fragilariopsis kerguelensis. Their results will contribute to parameterization of new ice sheet models that seek to reconstruct and forecast West Antarctic Ice Sheet behavior. This project will directly contribute to undergraduate education at an undergraduate-only college and at a public university that serves a demographic typified by first generation university students and underrepresented groups. Spanning geology, geochemistry, sedimentology, paleontology and paleoceanography, the proposed work will allow undergraduate students to develop diverse skills through hands-on research within a collaborative team that is dedicated to societally relevant research. The two graduate students will conduct original research and work alongside/mentor undergraduates, making for a well-rounded research experience that prepares them for success in future academic or employment sectors. The discoveries that come from this deep-sea record from West Antarctica will be communicated by students and investigators at national and international conferences and an array of public science outreach events.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -95.0, "geometry": "POINT(-107.5 -71.5)", "instruments": null, "is_usap_dc": true, "keywords": "ICEBERGS; SEA SURFACE TEMPERATURE; Amundsen Sea; MICROFOSSILS", "locations": "Amundsen Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY; PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE \u003e PLIOCENE", "persons": "Scherer, Reed Paul", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.0, "title": "Collaborative Research: Testing the Linchpin of WAIS Collapse with Diatoms and IRD in Pleistocene and Late Pliocene Strata of the Resolution Drift, Amundsen Sea, Antarctica", "uid": "p0010451", "west": -120.0}, {"awards": "2224760 Gooseff, Michael", "bounds_geometry": "POINT(162.87 -77)", "dataset_titles": "EDI Data Portal: McMurdo Dry Valleys LTER", "datasets": [{"dataset_uid": "200379", "doi": "", "keywords": null, "people": null, "repository": "Environmental Data Initiative (EDI)", "science_program": null, "title": "EDI Data Portal: McMurdo Dry Valleys LTER", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=MCM"}], "date_created": "Tue, 14 Nov 2023 00:00:00 GMT", "description": "In this iteration of the McMurdo LTER project (MCM6), the project team will test ecological connectivity and stability theory in a system subject to strong physical drivers (geological legacies, extreme seasonality, and contemporary climate change) and driven by microbial organisms. Since microorganisms regulate most of the world\u0027s critical biogeochemical functions, these insights will be relevant far beyond polar ecosystems and will inform understanding and expectations of how natural and managed ecosystems respond to ongoing anthropogenic global change. MCM6 builds on previous foundational research, both in Antarctica and within the LTER network, to consider the temporal aspects of connectivity and how it relates to ecosystem stability. The project will examine how changes in the temporal variability of ecological connectivity interact with the legacies of the existing landscape that have defined habitats and biogeochemical cycling for millennia. The project team hypothesizes that the structure and functioning of the MDV ecosystem is dependent upon legacies and the contemporary frequency, duration, and magnitude of ecological connectivity. This hypothesis will be tested with new and continuing monitoring, experiments, and analyses of long-term datasets to examine: 1) the stability of these ecosystems as reflected by sentinel taxa, 2) the relationship between ecological legacies and ecosystem resilience, 3) the importance of material carryover during periods of low connectivity to maintaining biological activity and community stability, and 4) how changes in disturbance dynamics disrupt ecological cycles through the polar night. Tests of these hypotheses will occur in field and modeling activities using new and long-term datasets already collected. New datasets resulting from field activities will be made freely available via widely-known online databases (MCM LTER and EDI). The project team has also developed six Antarctic Core Ideas that encompass themes from data literacy to polar food webs and form a consistent thread across the education and outreach activities. Building on past success, collaborations will be established with teachers and artists embedded within the science teams, who will work to develop educational modules with science content informed by direct experience and artistic expression. Undergraduate mentoring efforts will incorporate computational methods through a new data-intensive scientific training program for MCM REU students. The project will also establish an Antarctic Research Experience for Community College Students at CU Boulder, to provide an immersive educational and research experience for students from diverse backgrounds in community colleges. MCM LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science and stewardship. Historically underrepresented participation will be expanded at each level of the project. To aid in these efforts, the project has established Education \u0026 Outreach and Diversity, Equity, and Inclusion committees to lead, coordinate, support, and integrate these activities through all aspects of MCM6.", "east": 162.87, "geometry": "POINT(162.87 -77)", "instruments": null, "is_usap_dc": true, "keywords": "COMMUNITY DYNAMICS; ABLATION ZONES/ACCUMULATION ZONES; SOIL TEMPERATURE; DIATOMS; FIELD INVESTIGATION; PERMANENT LAND SITES; BUOYS; GROUND-BASED OBSERVATIONS; SEDIMENTS; SNOW WATER EQUIVALENT; SPECIES/POPULATION INTERACTIONS; WATER-BASED PLATFORMS; FIXED OBSERVATION STATIONS; VIRUSES; PHYTOPLANKTON; ACTIVE LAYER; FIELD SURVEYS; RADIO TRANSMITTERS; DATA COLLECTIONS; ECOLOGICAL DYNAMICS; LANDSCAPE; GROUND WATER; SNOW/ICE CHEMISTRY; LAND-BASED PLATFORMS; ANIMALS/INVERTEBRATES; ECOSYSTEM FUNCTIONS; HUMIDITY; GEOCHEMISTRY; SURFACE WINDS; RIVERS/STREAM; GLACIER MASS BALANCE/ICE SHEET MASS BALANCE; SNOW; LAND RECORDS; ATMOSPHERIC PRESSURE; SURFACE TEMPERATURE; ATMOSPHERIC RADIATION; BACTERIA/ARCHAEA; AIR TEMPERATURE; GLACIERS; SNOW/ICE TEMPERATURE; SOIL CHEMISTRY; METEOROLOGICAL STATIONS; WATER QUALITY/WATER CHEMISTRY; TERRESTRIAL ECOSYSTEMS; MOORED; PROTISTS; STREAMFLOW STATION; Dry Valleys; LAKE/POND; LAKE ICE; SNOW DEPTH; AQUATIC ECOSYSTEMS; SNOW DENSITY; FIELD SITES", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Gooseff, Michael N.; Adams, Byron; Barrett, John; Diaz, Melisa A.; Doran, Peter; Dugan, Hilary A.; Mackey, Tyler; Morgan-Kiss, Rachael; Salvatore, Mark; Takacs-Vesbach, Cristina; Zeglin, Lydia H.", "platforms": "LAND-BASED PLATFORMS; LAND-BASED PLATFORMS \u003e FIELD SITES; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e DATA COLLECTIONS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e RADIO TRANSMITTERS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e METEOROLOGICAL STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e STREAMFLOW STATION; WATER-BASED PLATFORMS; WATER-BASED PLATFORMS \u003e BUOYS; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e BUOYS", "repo": "Environmental Data Initiative (EDI)", "repositories": "Environmental Data Initiative (EDI)", "science_programs": "LTER", "south": -77.0, "title": "LTER: MCM6 - The Roles of Legacy and Ecological Connectivity in a Polar Desert Ecosystem", "uid": "p0010440", "west": 162.87}, {"awards": "2149070 Hawco, Nicholas", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 13 Mar 2023 00:00:00 GMT", "description": "This proposal represents collaborative research to explore manganese (Mn) limitation in Antarctic diatoms by two early career investigators. Diatoms are central players in the Southern Ocean carbon cycle, where the micronutrient chemistry is fundamentally different from other oceans. The Southern Ocean is characterized by widespread low Mn, coupled with high zinc (Zn). High Zn levels are potentially toxic to diatoms as Zn can competitively inhibit Mn uptake and metabolism, compromising the ability of building critical cellular components, thus impacting the biological pump. Using culture experiments with a matrix of micronutrient treatments (Mn, Zn, Fe) and irradiances, and using physiological and transcriptomic approaches, along with biochemical principles, the Principal Investigators will address the central hypothesis (that diatoms from the Southern Ocean possess unique physiological mechanisms to adapt to low Mn/high Zn) by quantifying rates of uptake and transporter binding constants. The transcriptomics approach will help to identify candidate genes that may provide Antarctic diatoms physiological mechanisms in low Mn/high Zn environment. The project does not require fieldwork but instead would make use of culture experiments with 4 diatom species (3 Antarctic, and 1 temperate). The proposed approach will also enable the goal of developing biomarker(s) for assessing Mn stress or Zn toxicity and results from the physiological experiments will help parameterize models of micronutrient limitation in the Southern Ocean.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; BIOGEOCHEMICAL CYCLES; TRACE ELEMENTS; DIATOMS; Iron; Phytoplankton", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hawco, Nicholas; Cohen, Natalie", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA: Collaborative Research: Adaptations of Southern Ocean Diatoms to Manganese Scarcity: Can Physiological Ingenuity Overcome Unfavorable Chemistry?", "uid": "p0010412", "west": -180.0}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments; ODP Site 1098 deglacial diatom assemblage; Sediment chemistry of ODP Site 1098", "datasets": [{"dataset_uid": "601777", "doi": "10.15784/601777", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Sediment Core Data", "people": "Dove, Isabel", "repository": "USAP-DC", "science_program": null, "title": "ODP Site 1098 deglacial diatom assemblage", "url": "https://www.usap-dc.org/view/dataset/601777"}, {"dataset_uid": "601778", "doi": "10.15784/601778", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "people": "Dove, Isabel", "repository": "USAP-DC", "science_program": null, "title": "Sediment chemistry of ODP Site 1098", "url": "https://www.usap-dc.org/view/dataset/601778"}, {"dataset_uid": "601727", "doi": "10.15784/601727", "keywords": "Antarctica", "people": "Dove, Isabel", "repository": "USAP-DC", "science_program": null, "title": "Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments", "url": "https://www.usap-dc.org/view/dataset/601727"}], "date_created": "Wed, 28 Jul 2021 00:00:00 GMT", "description": "The chemical composition of diatom fossils in the Southern Ocean provides information about the environmental history of Antarctica, including sea ice extent, biological production, and ocean nutrient distribution. The sea ice zone is an important habitat for a group of diatoms, largely from the genus Chaetoceros, that have a unique life cycle stage under environmental stress, when they produce a structure called a resting spore. Resting spores are meant to reseed the surface ocean when conditions are more favorable. The production of these heavy resting spores tends to remove significant amounts of carbon and silicon, essential nutrients, out of the surface ocean. As a result, this group has the potential to remove carbon from the surface ocean and can impact the sedimentary record scientists use to reconstruct environmental change. \r\n\r\nThis project explores the role of resting spores and nutrients in the sedimentary record using the nitrogen isotopic signature of these fossils and how those measurements are used to estimate carbon cycle changes. Measurements of nitrogen stable isotopes of nitrate, biomass, and diatom-bound nitrogen and silicon-to-nitrogen ratios of individual species grown in the laboratory are used to quantify how resting spores record nutrient drawdown in the water column and to what degree their signature is biased toward low nutrient conditions. Laboratory incubations were conducted with surface sediment containing Chaetoceros spp.. The emergence of vegetative cells and subsequent formation of resting spores is manipulated with the addition of nutrients, primarily nitrate. The resulting samples, both of vegetative cells and resting spores were measured for diatom-bound d15N. Resting spore d15N values are consistently lower than the vegetative d15N \r\n from the same incubations. The incubation results will be used to quantify nutrient drawdown in sea ice environments during two contrasting intervals in earth history, the last ice age and the warm Pliocene. The project provided training and research opportunities for undergraduate and graduate students. Research efforts in Antarctic earth sciences are disseminated through an interactive display at the home institution and during university sponsored events.\r\n\r\nThis work addresses uncertainties in how Chaetoceros resting spores record surface nutrient conditions in their nitrogen stable isotopic composition, the relative impact of their specific signal with respect to the full sedimentary assemblage, and their potential to bias or enhance environmental reconstructions in the sea ice zone. \r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; USAP-DC; Antarctica; ISOTOPES; MARINE SEDIMENTS; LABORATORY; USA/NSF; NITROGEN; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Robinson, Rebecca", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "uid": "p0010234", "west": -180.0}, {"awards": "1543328 Van Mooy, Benjamin", "bounds_geometry": null, "dataset_titles": "Lipidomics of Antarctic waters. (TBD)", "datasets": [{"dataset_uid": "200149", "doi": "TBD", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Lipidomics of Antarctic waters. (TBD)", "url": "https://www.bco-dmo.org/data"}], "date_created": "Fri, 19 Jun 2020 00:00:00 GMT", "description": "The depletion of stratospheric ozone over Antarctica leads to abnormally high levels of ultraviolet radiation (UVR) from the sun reaching the surface of the ocean. This phenomenon is predicted to continue for the next half century, despite bans on ozone-destroying pollutants. Phytoplankton in the near surface ocean are subjected to variable amounts of UVR and contain a lot of lipids (fats). Because phytoplankton are at the base of the food chain their lipids makes their way into the Antarctic marine ecosystem\u0027s food web. The molecular structures of phytoplankton lipids are easily altered by UVR. When this happens, their lipids can be transformed from healthy molecules into potentially harmful molecules(oxylipins) known to be disruptive to reproductive and developmental processes. This project will use state-of-the-art molecular methods to answer questions about extent to which UVR damages lipid molecules in phytoplankton, and how these resultant molecules might effect the food chain in the ocean near Antarctica. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eLipid peroxidation is often invoked as consequence of increased exposure of phytoplankton to UVR-produced reactive oxygen species (ROS), but the literature is practically silent on peroxidized lipids and their byproducts (i.e. oxylipins) in the ocean. In waters of the West Antarctic Peninsula (WAP), spring-time blooms of diatoms contribute significantly to overall marine primary production. Oxylipins from diatoms can be highly bioactive; their impact on zooplankton grazers, bacteria, and other phytoplankton has been the subject of intense study. However, almost all of this work has focused on the production of oxylipins via enzymatic pathways, not by pathways involving UVR and/or ROS. Furthermore, rigorous experimental work on the effects of oxylipins has been confined almost exclusively to pure cultures and artificial communities. Thus, the true potential of these molecules to disrupt carbon cycling is very poorly-constrained, and is entirely unknown in the waters of the WAP. Armed with new highly-sensitive, state-of-the-art analytical techniques based on high-mass-resolution mass spectrometry, the principal investigator and his research group have begun to uncover an exquisite diversity of oxylipins in natural WAP planktonic communities. These techniques will be applied to understand the connections between UVR, ROS, oxylipins, and carbon cycling. The project will answer the question of how UVR, via ROS, affects oxylipin production by diatoms in WAP surface waters in controlled experiments conducted at a field station. With the answer to this question in hand, the project will also seek to answer how this phenomenon impacts the flow of carbon, particularly the export of organic carbon from the system, during a research cruise. The level of UVR-induced stresses experienced by oxylipin-rich planktonic communities in the WAP is unique, making Antarctica the only location for answering these fundamental questions. Major activities will include laboratory experiments with artificial membranes and diatom cultures, as well field experiments with phytoplankton, zooplankton, and bacteria in WAP waters.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Oxylipins; Palmer Station; UV Radiation; USAP-DC; West Antarctic Shelf; NOT APPLICABLE; AQUATIC SCIENCES; Phytoplankton", "locations": "West Antarctic Shelf; Palmer Station", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Van Mooy, Benjamin", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": null, "title": "Production and Fate of Oxylipins in Waters of the Western Antarctic Peninsula: Linkages Between UV Radiation, Lipid Peroxidation, and Carbon Cycling", "uid": "p0010109", "west": null}, {"awards": "1341464 Robinson, Rebecca; 1341432 Brzezinski, Mark", "bounds_geometry": "POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))", "dataset_titles": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments; Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S; Expedition Data of NBP1702; Particle composition measurements from along 170\u00b0W between 67-54\u00b0S; Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "datasets": [{"dataset_uid": "601523", "doi": "10.15784/601523", "keywords": "Antarctica; Biota; Carboy Growouts; Diatom; Diatom Assemblage Data; NBP1702; Oceans; R/v Nathaniel B. Palmer; Southern Ocean; Southern Ocean Summer", "people": "Robinson, Rebecca ; Riesselman, Christina; Jones, Colin; Robinson, Rebecca", "repository": "USAP-DC", "science_program": null, "title": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments", "url": "https://www.usap-dc.org/view/dataset/601523"}, {"dataset_uid": "601269", "doi": "10.15784/601269", "keywords": "Antarctica; Chlorophyll; Southern Ocean", "people": "Robinson, Rebecca; Brzezinski, Mark", "repository": "USAP-DC", "science_program": null, "title": "Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601269"}, {"dataset_uid": "601276", "doi": "10.15784/601276", "keywords": "Antarctica; Biogenic Silica; Nitrogen Isotopes; Southern Ocean", "people": "Brzezinski, Mark; Robinson, Rebecca", "repository": "USAP-DC", "science_program": null, "title": "Particle composition measurements from along 170\u00b0W between 67-54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601276"}, {"dataset_uid": "601562", "doi": "10.15784/601562", "keywords": "Antarctica; Biogenic Silica; Chemistry:sediment; Chemistry:Sediment; Lithogenic Silica; Marine Geoscience; NBP1702; Pore Water Biogeochemistry; Sediment; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Closset, Ivia; Brzezinski, Mark; Jones, Janice L.", "repository": "USAP-DC", "science_program": null, "title": "Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601562"}, {"dataset_uid": "200126", "doi": "10.7284/907211", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1702", "url": "https://www.rvdata.us/search/cruise/NBP1702"}, {"dataset_uid": "601576", "doi": "10.15784/601576", "keywords": "Antarctica; Biogenic Silica; Chemistry:sediment; Chemistry:Sediment; Diatom; Diatom Bound; Lithogenic Silica; Marine Geoscience; NBP1702; Nitrogen Isotopes; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Jones, Janice L.; Brzezinski, Mark; Robinson, Rebecca; Closset, Ivia", "repository": "USAP-DC", "science_program": null, "title": " Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601576"}, {"dataset_uid": "601522", "doi": "10.15784/601522", "keywords": "Antarctica; Nitrogen Isotopes; Oceans; Paleoproxies; Southern Ocean", "people": "Jones, Colin; Robinson, Rebecca ; Kelly, Roger; Closset, Ivia; Riesselman, Christina; Brzezinski, Mark; Robinson, Rebecca", "repository": "USAP-DC", "science_program": null, "title": "Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "url": "https://www.usap-dc.org/view/dataset/601522"}], "date_created": "Wed, 26 Feb 2020 00:00:00 GMT", "description": "The rise in atmospheric carbon dioxide concentrations and associated climate changes make understanding the role of the ocean in large scale carbon cycle a priority. Geologic samples allow exploration of potential mechanisms for carbon dioxide drawdown during glacial periods through the use of geochemical proxies. Nitrogen and silicon isotope signatures from fossil diatoms (microscopic plants) are used to investigate changes in the physical supply and biological demand for nutrients (like nitrogen and silicon and carbon) in the Southern Ocean. The project will evaluate the use the nitrogen and silicon isotope proxies through a series of laboratory experiments and Southern Ocean field sampling. The results will provide quantification of real relationships between nitrogen and silicon isotopes and nutrient usage in the Southern Ocean and allow exploration of the role of other factors, including biological diversity, ice cover, and mixing, in altering the chemical signatures recorded by diatoms. Seafloor sediment samples will be used to evaluate how well the signal created in the water column is recorded by fossil diatoms buried in the seafloor. Improving the nutrient isotope proxies will allow for a more quantitative understanding of the role of polar biology in regulating natural variation in atmospheric carbon dioxide. The project will also result in the training of a graduate student and development of outreach materials targeting a broad popular audience.\r\n\r\nThis project seeks to test the fidelity of the diatom nitrogen and silicon isotope proxies, two commonly used paleoceanographic tools for investigating the role of the Southern Ocean biological pump in regulating atmospheric CO2 concentrations on glacial-interglacial timescales. Existing ground-truthing data, including culture experiments, surface sediment data and downcore reconstructions, all suggest that nutrient utilization is the primary driver of isotopic variation in the Southern Ocean. However, strong contribution of interspecific variation is implied by recent culture results. Moreover, field and laboratory studies present some contradictory results in terms of the relative importance of interspecific variation and of inferred post-depositional alteration of the nutrient isotope signals. Here, a first order test of the N and Si diatom nutrient isotope paleo-proxies, involving water column dissolved and particulate sampling and laboratory culturing of field-isolates, is proposed. Southern Ocean water, biomass, live diatoms and fossil diatom sampling will be conducted to investigate species and assemblage related variability in diatom nitrogen and silicon isotopes and their relationship to surface nutrient fields and early diagenesis. Access to fresh materials produced in an analogous environmental context to the sediments of primary interest is critical for making robust paleoceanographic reconstructions. Field sampling will occur along 175\u00b0W, transecting the Antarctic Circumpolar Current from the subtropics to the marginal ice edge. Collection of water, sinking/suspended particles and multi-core samples from 13 stations and 3 shipboard incubation experiments will be used to test four proposed hypotheses that together evaluate the significance of existing culture results and seek to allow the best use of diatom nutrient isotope proxies in evaluating the biological pump.", "east": -165.0, "geometry": "POINT(-170 -60.5)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; AMD; NITROGEN ISOTOPES; R/V NBP; NSF/USA; NUTRIENTS; USAP-DC; Amd/Us", "locations": "Southern Ocean", "north": -54.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Robinson, Rebecca; Brzezinski, Mark", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "uid": "p0010083", "west": -175.0}, {"awards": "1643684 Saito, Mak; 1644073 DiTullio, Giacomo", "bounds_geometry": "POLYGON((-180 -72,-173.6 -72,-167.2 -72,-160.8 -72,-154.4 -72,-148 -72,-141.6 -72,-135.2 -72,-128.8 -72,-122.4 -72,-116 -72,-116 -72.7,-116 -73.4,-116 -74.1,-116 -74.8,-116 -75.5,-116 -76.2,-116 -76.9,-116 -77.6,-116 -78.3,-116 -79,-122.4 -79,-128.8 -79,-135.2 -79,-141.6 -79,-148 -79,-154.4 -79,-160.8 -79,-167.2 -79,-173.6 -79,180 -79,178 -79,176 -79,174 -79,172 -79,170 -79,168 -79,166 -79,164 -79,162 -79,160 -79,160 -78.3,160 -77.6,160 -76.9,160 -76.2,160 -75.5,160 -74.8,160 -74.1,160 -73.4,160 -72.7,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,172 -72,174 -72,176 -72,178 -72,-180 -72))", "dataset_titles": "Algal pigment concentrations from the Ross Sea; Biogenic silica concentrations from the Ross Sea; NBP1801 Expedition data; Nutrients from NBP18-01 CICLOPS", "datasets": [{"dataset_uid": "601205", "doi": "10.15784/601205", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Chlorophyll; Chromatography; Liquid Chromatograph; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Seawater Measurements; Southern Ocean; Water Measurements; Water Samples", "people": "Ditullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Algal pigment concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601205"}, {"dataset_uid": "601225", "doi": "10.15784/601225", "keywords": "Antarctica; Biogenic Silica; Biogenic Silica Concentrations; Chemistry:Water; Geochemistry; NBP1801; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Southern Ocean; Spectroscopy; Water Measurements; Water Samples", "people": "Ditullio, Giacomo; Schanke, Nicole", "repository": "USAP-DC", "science_program": null, "title": "Biogenic silica concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601225"}, {"dataset_uid": "200056", "doi": "10.7284/907753", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1801 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1801"}, {"dataset_uid": "601428", "doi": "10.15784/601428", "keywords": "Amundsen Sea; Antarctica; NBP1801; Nitrate; Nitrite; Nutrients; Phosphate; Ross Sea; R/v Nathaniel B. Palmer; Silicic Acid; Terra Nova Bay", "people": "Saito, Mak", "repository": "USAP-DC", "science_program": null, "title": "Nutrients from NBP18-01 CICLOPS", "url": "https://www.usap-dc.org/view/dataset/601428"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "Phytoplankton blooms in the coastal waters of the Ross Sea, Antarctica are typically dominated by either diatoms or Phaeocystis Antarctica (a flagellated algae that often can form large colonies in a gelatinous matrix). The project seeks to determine if an association of bacterial populations with Phaeocystis antarctica colonies can directly supply Phaeocystis with Vitamin B12, which can be an important co-limiting micronutrient in the Ross Sea. The supply of an essential vitamin coupled with the ability to grow at lower iron concentrations may put Phaeocystis at a competitive advantage over diatoms. Because Phaeocystis cells can fix more carbon than diatoms and Phaeocystis are not grazed as efficiently as diatoms, the project will help in refining understanding of carbon dynamics in the region as well as the basis of the food web webs. Such understanding also has the potential to help refine predictive ecological models for the region. The project will conduct public outreach activities and will contribute to undergraduate and graduate research. Engagement of underrepresented students will occur during summer student internships. A collaboration with Italian Antarctic researchers, who have been studying the Terra Nova Bay ecosystem since the 1980s, aims to enhance the project and promote international scientific collaborations. \u003cbr/\u003e\u003cbr/\u003eThe study will test whether a mutualistic symbioses between attached bacteria and Phaeocystis provides colonial cells a mechanism for alleviating chronic Vitamin B12 co-limitation effects thereby conferring them with a competitive advantage over diatom communities. The use of drifters in a time series study will provide the opportunity to track in both space and time a developing algal bloom in Terra Nova Bay and to determine community structure and the physiological nutrient status of microbial populations. A combination of flow cytometry, proteomics, metatranscriptomics, radioisotopic and stable isotopic labeling experiments will determine carbon and nutrient uptake rates and the role of bacteria in mitigating potential vitamin B12 and iron limitation. Membrane inlet and proton transfer reaction mass spectrometry will also be used to estimate net community production and release of volatile organic carbon compounds that are climatically active. Understanding how environmental parameters can influence microbial community dynamics in Antarctic coastal waters will advance an understanding of how changes in ocean stratification and chemistry could impact the biogeochemistry and food web dynamics of Southern Ocean ecosystems.", "east": 160.0, "geometry": "POINT(-158 -75.5)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; NBP1801; Amd/Us; USA/NSF; USAP-DC; NUTRIENTS; PIGMENTS; CHLOROPHYLL; R/V NBP; Ross Sea; AMD", "locations": "Ross Sea", "north": -72.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "DiTullio, Giacomo; Lee, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -79.0, "title": "Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay", "uid": "p0010045", "west": -116.0}, {"awards": "1401489 Sigman, Daniel", "bounds_geometry": "POLYGON((-180 -45,-144 -45,-108 -45,-72 -45,-36 -45,0 -45,36 -45,72 -45,108 -45,144 -45,180 -45,180 -47.5,180 -50,180 -52.5,180 -55,180 -57.5,180 -60,180 -62.5,180 -65,180 -67.5,180 -70,144 -70,108 -70,72 -70,36 -70,0 -70,-36 -70,-72 -70,-108 -70,-144 -70,-180 -70,-180 -67.5,-180 -65,-180 -62.5,-180 -60,-180 -57.5,-180 -55,-180 -52.5,-180 -50,-180 -47.5,-180 -45))", "dataset_titles": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age; Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.; Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.; GOSHIP section IO8S and P18S", "datasets": [{"dataset_uid": "200048", "doi": "doi.pangaea.de/10.1594/PANGAEA.891436.", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.", "url": "https://doi.pangaea.de/10.1594/PANGAEA.891436"}, {"dataset_uid": "200051", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age", "url": "https://www.pnas.org/content/suppl/2017/03/14/1615718114.DCSupplemental"}, {"dataset_uid": "200050", "doi": "", "keywords": null, "people": null, "repository": "CLIVAR", "science_program": null, "title": "GOSHIP section IO8S and P18S", "url": "https://cchdo.ucsd.edu/"}, {"dataset_uid": "200049", "doi": "doi.org/10.1594/PANGAEA.848271", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.", "url": "https://doi.org/10.1594/PANGAEA.848271"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "ABSTRACT\u003cbr/\u003eIntellectual Merit:\u003cbr/\u003eThe high concentration of the major nutrients nitrate and phosphate is a fundamental characteristic of the Antarctic Zone in the Southern Ocean and is central to its role in global ocean fertility and the global carbon cycle. The isotopic composition of diatom-bound organic nitrogen is one of the best hopes for reconstructing the nutrient status of polar surface waters over glacial cycles, which in turn may hold the explanation for the decline in atmospheric carbon dioxide during ice ages. The PIs propose to generate detailed diatom-bound nitrogen isotope (\u0026#948;15Ndb) records from high sedimentation rate cores from the Kerguelen Plateau. Because the cores were collected at relatively shallow seafloor depths, they have adequate planktonic and benthic foraminifera to develop accurate age models. The resulting data could be compared with climate records from Antarctic ice cores and other archives to investigate climate-related changes, including the major steps into and out of ice ages and the millennial-scale events that occur during ice ages and at their ends. The records generated in this project will provide a critical test of hypotheses for the cause of lower ice age CO2.\u003cbr/\u003e\u003cbr/\u003eBroader impacts:\u003cbr/\u003eThis study will contribute to the goal of understanding ice ages and past CO2 changes, which both have broad implications for future climate. Undergraduates will undertake summer internships, with the possibility of extending their work into junior year projects and senior theses. In addition, the PI will lead modules for two Princeton programs for middle school teachers and will host a teacher for a six-week summer research project.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; South Pacific Ocean; USAP-DC; NOT APPLICABLE", "locations": "South Pacific Ocean", "north": -45.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sigman, Daniel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "PANGAEA", "repositories": "CLIVAR; PANGAEA; Publication", "science_programs": null, "south": -70.0, "title": "High-resolution, Assemblage-specific Records of Diatom-bound N Isotopes from the Indian Sector of the Antarctic Ocean", "uid": "p0010046", "west": -180.0}, {"awards": "1443420 Dodd, Justin", "bounds_geometry": "POLYGON((167.07 -77.87,167.073 -77.87,167.076 -77.87,167.079 -77.87,167.082 -77.87,167.085 -77.87,167.088 -77.87,167.091 -77.87,167.094 -77.87,167.097 -77.87,167.1 -77.87,167.1 -77.873,167.1 -77.876,167.1 -77.879,167.1 -77.882,167.1 -77.885,167.1 -77.888,167.1 -77.891,167.1 -77.894,167.1 -77.897,167.1 -77.9,167.097 -77.9,167.094 -77.9,167.091 -77.9,167.088 -77.9,167.085 -77.9,167.082 -77.9,167.079 -77.9,167.076 -77.9,167.073 -77.9,167.07 -77.9,167.07 -77.897,167.07 -77.894,167.07 -77.891,167.07 -77.888,167.07 -77.885,167.07 -77.882,167.07 -77.879,167.07 -77.876,167.07 -77.873,167.07 -77.87))", "dataset_titles": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "datasets": [{"dataset_uid": "601220", "doi": "10.15784/601220", "keywords": "And-1B; Andrill; Antarctica; Chemistry:sediment; Chemistry:Sediment; Delta 18O; Diatom; Mass Spectrometer; Oxygen Isotope; Paleoclimate; Pliocene; Sediment; Wais Project; West Antarctic Ice Sheet", "people": "Dodd, Justin; Abbott, Tirzah", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "url": "https://www.usap-dc.org/view/dataset/601220"}], "date_created": "Tue, 06 Aug 2019 00:00:00 GMT", "description": "Abstract\u003cbr/\u003eDuring the Early Pliocene, 4.8 to 3.4 million years ago, warmer-than-present global temperatures resulted in a retreat of the Ross Ice Shelf and West Antarctic Ice Sheet. Understanding changes in ocean dynamics during times of reduced ice volume and increased temperatures in the geologic past will improve the predictive models for these conditions. The primary goal of the proposed research is to develop a new oxygen isotope record of Pliocene oceanographic conditions near the Antarctic continent. Oxygen isotope values from the carbonate tests of benthic foraminifera have become the global standard for paleo-oceanographic studies, but foraminifera are sparse in high-latitude sediment cores. This research will instead make use of oxygen isotope measurements from diatom silica preserved in a marine sediment core from the Ross Sea. The project is the first attempt at using this method and will advance understanding of global ocean dynamics and ice sheet-ocean interactions during the Pliocene. The project will foster the professional development of two early-career scientists and serve as training for graduate and undergraduate student researchers. The PIs will use this project to introduce High School students to polar/oceanographic research, as well as stable isotope geochemistry. Collaboration with teachers via NSTA and Polar Educators International will ensure the implementation of excellent STEM learning activities and curricula for younger students. \u003cbr/\u003e\u003cbr/\u003eTechnical Description\u003cbr/\u003eThis project will produce a high-resolution oxygen isotope record from well-dated diatom rich sediments that have been cross-correlated with global benthic foraminifera oxygen isotope records. Diatom silica frustules deposited during the Early Pliocene and recovered by the ANDRILL Project (AND-1B) provide ideal material for this objective. Diatomite unites in the AND-1B core are nearly pure, with little evidence of opal formation. A diatom oxygen isotope record from this core offers the potential to constrain lingering uncertainties about Ross Sea and Southern Ocean paleoceanography and Antarctic Ice Sheet history during a time of high atmospheric carbon dioxide concentrations. Specifically, oxygen isotope variations will be used to constrain changes in the water temperature and/or freshwater flux in the Pliocene Ross Sea. Diatom species data from the AND-1B core have been used to infer variations in the extent and duration of seasonal sea ice coverage, sea surface temperatures, and mid-water advection onto the continental shelf. However, the diatom oxygen isotope record will provide the first direct measure of water/oxygen isotope values at the Antarctic continental margin during the Pliocene.", "east": 167.1, "geometry": "POINT(167.085 -77.885)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "OXYGEN ISOTOPES; USAP-DC; Antarctica; NOT APPLICABLE", "locations": "Antarctica", "north": -77.87, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Dodd, Justin; Scherer, Reed Paul; Warnock, Jonathan", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.9, "title": "Diatom and Oxygen Isotope Evidence of Pliocene Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "uid": "p0010042", "west": 167.07}, {"awards": "1744645 Young, Jodi", "bounds_geometry": "POLYGON((-64.4 -64.2,-64.38 -64.2,-64.36 -64.2,-64.34 -64.2,-64.32 -64.2,-64.3 -64.2,-64.28 -64.2,-64.26 -64.2,-64.24 -64.2,-64.22 -64.2,-64.2 -64.2,-64.2 -64.26,-64.2 -64.32,-64.2 -64.38,-64.2 -64.44,-64.2 -64.5,-64.2 -64.56,-64.2 -64.62,-64.2 -64.68,-64.2 -64.74,-64.2 -64.8,-64.22 -64.8,-64.24 -64.8,-64.26 -64.8,-64.28 -64.8,-64.3 -64.8,-64.32 -64.8,-64.34 -64.8,-64.36 -64.8,-64.38 -64.8,-64.4 -64.8,-64.4 -64.74,-64.4 -64.68,-64.4 -64.62,-64.4 -64.56,-64.4 -64.5,-64.4 -64.44,-64.4 -64.38,-64.4 -64.32,-64.4 -64.26,-64.4 -64.2))", "dataset_titles": "Dataset: Particulate Organic Carbon and Particulate Nitrogen; Dataset: Photosynthetic Pigments; Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume; Sea-ice diatom compatible solute shifts", "datasets": [{"dataset_uid": "200378", "doi": "10.26008/1912/bco-dmo.913655.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume", "url": "https://www.bco-dmo.org/dataset/913655"}, {"dataset_uid": "200376", "doi": "10.26008/1912/bco-dmo.913566.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Particulate Organic Carbon and Particulate Nitrogen", "url": "https://www.bco-dmo.org/dataset/913566"}, {"dataset_uid": "200377", "doi": "10.26008/1912/bco-dmo.913222.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Photosynthetic Pigments", "url": "https://www.bco-dmo.org/dataset/913222"}, {"dataset_uid": "200322", "doi": "10.21228/M84386", "keywords": null, "people": null, "repository": "Metabolomics workbench", "science_program": null, "title": "Sea-ice diatom compatible solute shifts", "url": "https://www.metabolomicsworkbench.org/data/DRCCMetadata.php?Mode=Study\u0026StudyID=ST001393"}], "date_created": "Tue, 23 Jul 2019 00:00:00 GMT", "description": "Rapid changes in the extent and thickness of sea ice during the austral spring subject microorganisms within or attached to the ice to large fluctuations in temperature, salinity, light and nutrients. This project aims to identify cellular responses in sea-ice algae to increasing temperature and decreasing salinity during the spring melt along the western Antarctic Peninsula and to determine how associated changes at the cellular level can potentially affect dynamic, biologically driven processes. Understanding how sea-ice algae cope with, and are adapted to, their environment will not only help predict how polar ecosystems may change as the extent and thickness of sea ice change, but will also provide a better understanding of the widespread success of photosynthetic life on Earth. The scientific context and resulting advances from the research will be communicated to the general public through outreach activities that includes work with Science Communication Fellows and the popular Polar Science Weekend at the Pacific Science Center in Seattle, Washington. The project will provide student training to college students as well as provide for educational experiences for K-12 school children. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThere is currently a poor understanding of feedback relationships that exist between the rapidly changing environment in the western Antarctic Peninsula region and sea-ice algal production. The large shifts in temperature and salinity that algae experience during the spring melt affect critical cellular processes, including rates of enzyme-catalyzed reactions involved in photosynthesis and respiration, and the production of stress-protective compounds. These changes in cellular processes are poorly constrained but can be large and may have impacts on local ecosystem productivity and biogeochemical cycles. In particular, this study will focus on the thermal sensitivity of enzymes and the cycling of compatible solutes and exopolymers used for halo- and cryo-protection, and how they influence primary production and the biogeochemical cycling of carbon and nitrogen. Approaches will include field sampling during spring melt, incubation experiments of natural sea-ice communities under variable temperature and salinity conditions, and controlled manipulation of sea-ice algal species in laboratory culture. Employment of a range of techniques, from fast repetition rate fluorometry and gross and net photosynthetic measurements to metabolomics and enzyme kinetics, will tease apart the mechanistic effects of temperature and salinity on cell metabolism and primary production with the goal of quantifying how these changes will impact biogeochemical processes along the western Antarctic Peninsula.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -64.2, "geometry": "POINT(-64.3 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; SHIPS; DIATOMS; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -64.2, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Young, Jodi; Deming, Jody", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "BCO-DMO", "repositories": "BCO-DMO; Metabolomics workbench", "science_programs": null, "south": -64.8, "title": "Spring Blooms of Sea Ice Algae Along the Western Antarctic Peninsula: Effects of Warming and Freshening on Cell Physiology and Biogeochemical Cycles.", "uid": "p0010039", "west": -64.4}, {"awards": "1745036 Marchetti, Adrian; 1744760 Hopkinson, Brian", "bounds_geometry": "POLYGON((-77 -61,-75.2 -61,-73.4 -61,-71.6 -61,-69.8 -61,-68 -61,-66.2 -61,-64.4 -61,-62.6 -61,-60.8 -61,-59 -61,-59 -62.1,-59 -63.2,-59 -64.3,-59 -65.4,-59 -66.5,-59 -67.6,-59 -68.7,-59 -69.8,-59 -70.9,-59 -72,-60.8 -72,-62.6 -72,-64.4 -72,-66.2 -72,-68 -72,-69.8 -72,-71.6 -72,-73.4 -72,-75.2 -72,-77 -72,-77 -70.9,-77 -69.8,-77 -68.7,-77 -67.6,-77 -66.5,-77 -65.4,-77 -64.3,-77 -63.2,-77 -62.1,-77 -61))", "dataset_titles": "Photosynthetic physiological data of Proteorhodopsin containing diatoms under differing iron availabilities", "datasets": [{"dataset_uid": "601530", "doi": "10.15784/601530", "keywords": "Antarctica; Diatom", "people": "Hopkinson, Brian; Andrew, Sarah; Marchetti, Adrian; Plumb, Kaylie", "repository": "USAP-DC", "science_program": null, "title": "Photosynthetic physiological data of Proteorhodopsin containing diatoms under differing iron availabilities", "url": "https://www.usap-dc.org/view/dataset/601530"}], "date_created": "Sun, 16 Jun 2019 00:00:00 GMT", "description": "Proteorhodopsins (PR) are retinal-binding membrane proteins that can act as light-driven proton pumps to generate energy that can be used for metabolism and growth. The discovery of PRs in many diverse marine prokaryotic microbes has initiated extensive investigations into their distributions and functional roles. Recently, a rhodopsin-like gene of the proton-pumping variety was identified in diatoms thus revealing their presence within obligate marine eukaryotic photoautotrophs. Since this time, PRs have been identified in a number of diatom isolates although there appears to be a much higher frequency of\r\nPR in diatoms residing in cold, iron-limited regions of the ocean, particularly in the Southern Ocean (SO). PR is especially suited for use in SO phytoplankton since unlike conventional photosynthesis, it uses no iron and its reaction rate is insensitive to temperature. The overall objective of our proposed project is to characterize Antarctic diatom-PR and determine its role in the adaptation of SO diatoms to the prevailing conditions of low iron concentrations and extremely low temperatures. Our research objectives will be achieved through a combination of molecular, biochemical and physiological measurements in diatom isolates recently obtained from the Western Antarctic Peninsula region. We will determine the proton-pumping characteristics and pumping rates of PR as a function of light intensity and wavelength, the resultant PR-linked intracellular ATP production rates, and the cellular localization of the protein. We will examine under which environmental conditions Antarctic diatom-PR is most highly expressed and construct a cellular energy budget that includes diatom-PR when grown under these different growth conditions. Estimates of the energy flux generated by PR in PR-containing diatoms will be compared to total energy generation by the photosynthetic light reactions and metabolically coupled respiration rates. Finally, we will compare the characteristics and gene expression of diatom-PR in Antarctic diatoms to PR-containing diatoms isolated from temperate regions in order to investigate if there is a preferential dependence on energy production through diatom-PR in diatoms residing in cold, iron-limited regions of the ocean.", "east": -59.0, "geometry": "POINT(-68 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; NSF/USA; Southern Ocean; AMD; Amd/Us; LABORATORY; USAP-DC; BIOGEOCHEMICAL CYCLES", "locations": "Southern Ocean", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Marchetti, Adrian; Septer, Alecia; Hopkinson, Brian", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.0, "title": "Collaborative research: Antarctic diatom proteorhodopsins: Characterization and a potential role in the iron-limitation response", "uid": "p0010033", "west": -77.0}, {"awards": "1341479 Marchetti, Adrian", "bounds_geometry": "POLYGON((-72.8 -48,-67.12 -48,-61.44 -48,-55.76 -48,-50.08 -48,-44.4 -48,-38.72 -48,-33.04 -48,-27.36 -48,-21.68 -48,-16 -48,-16 -50.02,-16 -52.04,-16 -54.06,-16 -56.08,-16 -58.1,-16 -60.12,-16 -62.14,-16 -64.16,-16 -66.18,-16 -68.2,-21.68 -68.2,-27.36 -68.2,-33.04 -68.2,-38.72 -68.2,-44.4 -68.2,-50.08 -68.2,-55.76 -68.2,-61.44 -68.2,-67.12 -68.2,-72.8 -68.2,-72.8 -66.18,-72.8 -64.16,-72.8 -62.14,-72.8 -60.12,-72.8 -58.1,-72.8 -56.08,-72.8 -54.06,-72.8 -52.04,-72.8 -50.02,-72.8 -48))", "dataset_titles": "16S and 18S Sequence data; Fragilariopsis kerguelensis iron and light transcriptomes; Physiology and transcriptomes of polar isolates; Polar isolate transcriptomes; Sequence data from Ocean Station Papa seawater ; Sequence data RNA-Seq of marine phytoplankton: FeB12", "datasets": [{"dataset_uid": "200018", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Sequence data from Ocean Station Papa seawater ", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP006906"}, {"dataset_uid": "200017", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Sequence data RNA-Seq of marine phytoplankton: FeB12", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP074366"}, {"dataset_uid": "200016", "doi": "", "keywords": null, "people": null, "repository": "iMicrobe", "science_program": null, "title": "Fragilariopsis kerguelensis iron and light transcriptomes", "url": "https://www.imicrobe.us/#/projects/104"}, {"dataset_uid": "200020", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Physiology and transcriptomes of polar isolates", "url": "https://www.bco-dmo.org/project/653229"}, {"dataset_uid": "200019", "doi": "", "keywords": null, "people": null, "repository": "Cyverse Data Commons", "science_program": null, "title": "Polar isolate transcriptomes", "url": "http://datacommons.cyverse.org/search/?search_term=unc_phyto_isolates"}, {"dataset_uid": "200021", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "16S and 18S Sequence data", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA299401"}], "date_created": "Mon, 11 Mar 2019 00:00:00 GMT", "description": "The Southern Ocean surrounding Antarctica is changing rapidly in response to Earth\u0027s warming climate. These changes will undoubtedly influence communities of primary producers (the organisms at the base of the food chain, particularly plant-like organisms using sunlight for energy) by altering conditions that influence their growth and composition. Because primary producers such as phytoplankton play an important role in global biogeochemical cycling, it is essential to understand how they will respond to changes in their environment. The growth of phytoplankton in certain regions of the Southern Ocean is constrained by steep gradients in chemical and physical properties that vary in both space and time. Light and iron have been identified as key variables influencing phytoplankton abundance and distribution within Antarctic waters. Microscopic algae known as diatoms are dominant members of the phytoplankton and sea ice communities, accounting for significant proportions of primary production. The overall objective of this project is to identify the molecular bases for the physiological responses of polar diatoms to varying light and iron conditions. The project should provide a means of evaluating the extent these factors regulate diatom growth and influence net community productivity in Antarctic waters. Although numerous studies have investigated how polar diatoms are affected by varying light and iron, the cellular mechanisms leading to their distinct physiological responses remain unknown. We observed several growth responses, but a majority of polar diatom growth rates and photophysiology did not appear to be co-limited by iron and light limitation. Using comparative transcriptomics, we have examined the expression patterns of key genes and metabolic pathways in several ecologically important polar diatoms isolated from Antarctic waters and grown under varying iron and irradiance conditions. In addition, molecular indicators for iron and light limitation will be developed within these polar diatoms through the identification of iron- and light-responsive genes -- the expression patterns of which can be used to determine their physiological status. Upon verification in laboratory cultures, these indicators will be utilized by way of metatranscriptomic sequencing to examine iron and light limitation in natural diatom assemblages collected along environmental gradients in Western Antarctic Peninsula waters. In order to fully understand the role phytoplankton play in Southern Ocean biogeochemical cycles, dependable methods that provide a means of elucidating the physiological status of phytoplankton at any given time and location are essential.", "east": -16.0, "geometry": "POINT(-44.4 -58.1)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; AQUATIC SCIENCES; PHYTOPLANKTON; USAP-DC; Southern Ocean; Sea Surface; DIATOMS", "locations": "Sea Surface; Southern Ocean", "north": -48.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Marchetti, Adrian", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "BCO-DMO; Cyverse Data Commons; iMicrobe; NCBI GenBank", "science_programs": null, "south": -68.2, "title": "Iron and Light Limitation in Ecologically Important Polar Diatoms: Comparative Transcriptomics and Development of Molecular Indicators", "uid": "p0010018", "west": -72.8}, {"awards": "0838947 Tulaczyk, Slawek; 0839142 Tulaczyk, Slawek; 0839107 Powell, Ross; 0838764 Anandakrishnan, Sridhar; 0838855 Jacobel, Robert; 0839059 Powell, Ross; 0838763 Anandakrishnan, Sridhar", "bounds_geometry": null, "dataset_titles": "Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line; Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD); Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES); IRIS ID#s 201035, 201162, 201205; IRIS offers free and open access to a comprehensive data store of raw geophysical time-series data collected from a large variety of sensors, courtesy of a vast array of US and International scientific networks, including seismometers (permanent and temporary), tilt and strain meters, infrasound, temperature, atmospheric pressure and gravimeters, to support basic research aimed at imaging the Earth\u0027s interior.; Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set; Paleogene marine and terrestrial development of the West Antarctic Rift System: Palynomorph Data Set; Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone; The IRIS DMC archives and distributes data to support the seismological research community.; UNAVCO ID#s WHL1, WHL2, LA02, LA09 (full data link not provided)", "datasets": [{"dataset_uid": "601234", "doi": "10.15784/601234", "keywords": "ACL; Antarctica; Biomarker; BIT Index; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Stream; Whillans Ice Stream; WISSARD", "people": "Casta\u00f1eda, Isla; Scherer, Reed Paul; Askin, Rosemary; Baudoin, Patrick; Warny, Sophie; Coenen, Jason", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set", "url": "https://www.usap-dc.org/view/dataset/601234"}, {"dataset_uid": "600155", "doi": "10.15784/600155", "keywords": "Antarctica; Glaciology; Oceans; Southern Ocean; WISSARD", "people": "Powell, Ross", "repository": "USAP-DC", "science_program": null, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES)", "url": "https://www.usap-dc.org/view/dataset/600155"}, {"dataset_uid": "600154", "doi": "10.15784/600154", "keywords": "Antarctica; Biota; Diatom; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Lake Whillans; Paleoclimate; Ross Sea; Southern Ocean; Subglacial Lake; WISSARD", "people": "Powell, Ross", "repository": "USAP-DC", "science_program": null, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD)", "url": "https://www.usap-dc.org/view/dataset/600154"}, {"dataset_uid": "001405", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS offers free and open access to a comprehensive data store of raw geophysical time-series data collected from a large variety of sensors, courtesy of a vast array of US and International scientific networks, including seismometers (permanent and temporary), tilt and strain meters, infrasound, temperature, atmospheric pressure and gravimeters, to support basic research aimed at imaging the Earth\u0027s interior.", "url": "http://www.iris.edu/hq/data_and_software"}, {"dataset_uid": "001406", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "The IRIS DMC archives and distributes data to support the seismological research community.", "url": "http://ds.iris.edu/ds/nodes/dmc/"}, {"dataset_uid": "609594", "doi": "10.7265/N54J0C2W", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; GPS; Radar; Whillans Ice Stream", "people": "Jacobel, Robert", "repository": "USAP-DC", "science_program": null, "title": "Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone", "url": "https://www.usap-dc.org/view/dataset/609594"}, {"dataset_uid": "601122", "doi": "10.15784/601122", "keywords": "Antarctica; Flexure Zone; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Ice-Shelf Basal Melting; Ice-Shelf Strain Rate", "people": "Begeman, Carolyn", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line", "url": "https://www.usap-dc.org/view/dataset/601122"}, {"dataset_uid": "000148", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS ID#s 201035, 201162, 201205", "url": "http://ds.iris.edu/"}, {"dataset_uid": "000150", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "UNAVCO ID#s WHL1, WHL2, LA02, LA09 (full data link not provided)", "url": "http://www.unavco.org/"}, {"dataset_uid": "601245", "doi": "10.15784/601245", "keywords": "Antarctica; Pollen; West Antarctica; WISSARD", "people": "Casta\u00f1eda, Isla; Coenen, Jason; Askin, Rosemary; Scherer, Reed Paul; Warny, Sophie; Baudoin, Patrick", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Paleogene marine and terrestrial development of the West Antarctic Rift System: Palynomorph Data Set", "url": "https://www.usap-dc.org/view/dataset/601245"}], "date_created": "Mon, 10 Sep 2018 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The LISSARD project (Lake and Ice Stream Subglacial Access Research Drilling) is one of three research components of the WISSARD integrative initiative (Whillans Ice Stream Subglacial Access Research Drilling) that is being funded by the Antarctic Integrated System Science Program of NSF\u0027s Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The LISSARD component of WISSARD focuses on the role of active subglacial lakes in determining how fast the West Antarctic ice sheet loses mass to the global ocean and influences global sea level changes. The importance of Antarctic subglacial lakes has only been recently recognized, and the lakes have been identified as high priority targets for scientific investigations because of their unknown contributions to ice sheet stability under future global warming scenarios. LISSARD has several primary science goals: A) To provide an observational basis for improving treatments of subglacial hydrological and mechanical processes in models of ice sheet mass balance and stability; B) To reconstruct the past history of ice stream stability by analyzing archives of past basal water and ice flow variability contained in subglacial sediments, porewater, lake water, and basal accreted ice; C) To provide background understanding of subglacial lake environments to benefit RAGES and GBASE (the other two components of the WISSARD project); and D) To synthesize data and concepts developed as part of this project to determine whether subglacial lakes play an important role in (de)stabilizing Antarctic ice sheets. We propose an unprecedented synthesis of approaches to studying ice sheet processes, including: (1) satellite remote sensing, (2) surface geophysics, (3) borehole observations and measurements and, (4) basal and subglacial sampling. \u003cbr/\u003e\u003cbr/\u003eINTELLECTUAL MERIT: The latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations. \u003cbr/\u003e\u003cbr/\u003eBROADER IMPACTS: Societal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": true, "keywords": "USAP-DC; Ice Penetrating Radar; Antarctic; Subglacial Lake; Subglacial Hydrology; Grounding Line; Sea Level Rise; Bed Reflectivity; Ice Sheet Stability; Stability; Radar; Sub-Ice-Shelf; Geophysics; Biogeochemical; LABORATORY; Sediment; Sea Floor Sediment; Ice Thickness; Model; Ice Stream Stability; Basal Ice; SATELLITES; Ice Sheet Thickness; Subglacial; Antarctica; NOT APPLICABLE; Antarctic Ice Sheet; Ice Sheet; FIELD SURVEYS; Surface Elevation; Geochemistry; FIELD INVESTIGATION; Not provided", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Tulaczyk, Slawek; Fisher, Andrew; Powell, Ross; Anandakrishnan, Sridhar; Jacobel, Robert; Scherer, Reed Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES", "repo": "USAP-DC", "repositories": "IRIS; UNAVCO; USAP-DC", "science_programs": "WISSARD", "south": null, "title": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)", "uid": "p0000105", "west": null}, {"awards": "0732655 Mosley-Thompson, Ellen; 0732602 Truffer, Martin; 0732983 Vernet, Maria; 0732711 Smith, Craig; 0732651 Gordon, Arnold; 0732625 Leventer, Amy", "bounds_geometry": "POLYGON((-68 -57.8,-66.78 -57.8,-65.56 -57.8,-64.34 -57.8,-63.12 -57.8,-61.9 -57.8,-60.68 -57.8,-59.46 -57.8,-58.24 -57.8,-57.02 -57.8,-55.8 -57.8,-55.8 -58.8,-55.8 -59.8,-55.8 -60.8,-55.8 -61.8,-55.8 -62.8,-55.8 -63.8,-55.8 -64.8,-55.8 -65.8,-55.8 -66.8,-55.8 -67.8,-57.02 -67.8,-58.24 -67.8,-59.46 -67.8,-60.68 -67.8,-61.9 -67.8,-63.12 -67.8,-64.34 -67.8,-65.56 -67.8,-66.78 -67.8,-68 -67.8,-68 -66.8,-68 -65.8,-68 -64.8,-68 -63.8,-68 -62.8,-68 -61.8,-68 -60.8,-68 -59.8,-68 -58.8,-68 -57.8))", "dataset_titles": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems; Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203; Bruce Plateau Accumulation O18 2009-1900; Easten Antarctic Peninsula Surface Sediment Diatom Data; LMG13-11 JKC-1 Paleoceanographic data; Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; NBP1001 cruise data; NBP1203 cruise data; Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf; Sediment samples (full data link not provided)", "datasets": [{"dataset_uid": "000226", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203", "url": "https://doi.org/10.1594/ieda/320821"}, {"dataset_uid": "000143", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1203 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "000142", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1001 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1001"}, {"dataset_uid": "600167", "doi": "10.15784/600167", "keywords": "Antarctica; Antarctic Peninsula; Bruce Plateau; Glaciology; Ice Core Records; Isotope; LARISSA; Paleoclimate; Sample/collection Description; Sample/Collection Description; Snow Accumulation", "people": "Thompson, Lonnie G.; Mosley-Thompson, Ellen", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Bruce Plateau Accumulation O18 2009-1900", "url": "https://www.usap-dc.org/view/dataset/600167"}, {"dataset_uid": "601211", "doi": "10.15784/601211", "keywords": "Antarctica; Antarctic Peninsula; Benthos; Biota; Diatom; Geology/Geophysics - Other; LMG0502; Marine Geoscience; Marine Sediments; Microscope; NBP0003; NBP0107; NBP0603; NBP1203; R/v Nathaniel B. Palmer; Surface Sediment", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Easten Antarctic Peninsula Surface Sediment Diatom Data", "url": "https://www.usap-dc.org/view/dataset/601211"}, {"dataset_uid": "000145", "doi": "", "keywords": null, "people": null, "repository": "AMGRF", "science_program": null, "title": "Sediment samples (full data link not provided)", "url": "http://arf.fsu.edu/"}, {"dataset_uid": "600073", "doi": "10.15784/600073", "keywords": "Antarctica; Antarctic Peninsula; Araon1304; Biota; LARISSA; Larsen B Ice Shelf; NBP1001; NBP1203; Oceans; Physical Oceanography; Southern Ocean; Weddell Sea", "people": "Vernet, Maria", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems", "url": "https://www.usap-dc.org/view/dataset/600073"}, {"dataset_uid": "601485", "doi": "10.15784/601485", "keywords": "Antarctica; Antarctic Peninsula; Delta 13C; Delta 18O; Paleoceanography; Temperature", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": "LARISSA", "title": "LMG13-11 JKC-1 Paleoceanographic data", "url": "https://www.usap-dc.org/view/dataset/601485"}, {"dataset_uid": "601348", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601348"}, {"dataset_uid": "601347", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601347"}, {"dataset_uid": "601346", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601346"}, {"dataset_uid": "601345", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601345"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "Taylor, Richard; DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601336"}, {"dataset_uid": "601306", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601306"}, {"dataset_uid": "601305", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601305"}], "date_created": "Thu, 01 Feb 2018 00:00:00 GMT", "description": "Like no other region on Earth, the northern Antarctic Peninsula represents a spectacular natural laboratory of climate change and provides the opportunity to study the record of past climate and ecological shifts alongside the present-day changes in one of the most rapidly warming regions on Earth. This award supports the cryospheric and oceano-graphic components of an integrated multi-disciplinary program to address these rapid and fundamental changes now taking place in Antarctic Peninsula (AP). By making use of a marine research platform (the RV NB Palmer and on-board helicopters) and additional logistical support from the Argentine Antarctic program, the project will bring glaciologists, oceanographers, marine geologists and biologists together, working collaboratively to address fundamentally interdisciplinary questions regarding climate change. The project will include gathering a new, high-resolution paleoclimate record from the Bruce Plateau of Graham Land, and using it to compare Holocene- and possibly glacial-epoch climate to the modern period; investigating the stability of the remaining Larsen Ice Shelf and rapid post-breakup glacier response ? in particular, the roles of surface melt and ice-ocean interactions in the speed-up and retreat; observing the contribution of, and response of, oceanographic systems to ice shelf disintegration and ice-glacier interactions. Helicopter support on board will allow access to a wide range of glacial and geological areas of interest adjacent to the Larsen embayment. At these locations, long-term in situ glacial monitoring, isostatic uplift, and ice flow GPS sites will be established, and high-resolution ice core records will be obtained using previously tested lightweight drilling equipment. Long-term monitoring of deep water outflow will, for the first time, be integrated into changes in ice shelf extent and thickness, bottom water formation, and multi-level circulation by linking near-source observations to distal sites of concentrated outflow. The broader impacts of this international, multidisciplinary effort are that it will significantly advance our understanding of linkages amongst the earth\u0027s systems in the Polar Regions, and are proposed with international participation (UK, Spain, Belgium, Germany and Argentina) and interdisciplinary engagement in the true spirit of the International Polar Year (IPY). It will also provide a means of engaging and educating the public in virtually all aspects of polar science and the effects of ongoing climate change. The research team has a long record of involving undergraduates in research, educating high-performing graduate students, and providing innovative and engaging outreach products to the K-12 education and public media forums. Moreover, forging the new links both in science and international Antarctic programs will provide a continuing legacy, beyond IPY, of improved understanding and cooperation in Antarctica.", "east": -55.8, "geometry": "POINT(-61.9 -62.8)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e BOX CORE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ICE AUGERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SNOW DENSITY CUTTER", "is_usap_dc": true, "keywords": "Paleoclimate; Megafauna; USAP-DC; AMD; Amd/Us; Antarctica; Climate Change; LABORATORY; Climate Variability; Multi-Disciplinary; Cryosphere; NBP1001; FIELD SURVEYS; Not provided; Antarctic Peninsula; R/V NBP; FIELD INVESTIGATION; USA/NSF; Ice Core; Holocene", "locations": "Antarctica; Antarctic Peninsula", "north": -57.8, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Truffer, Martin; Gordon, Arnold; Huber, Bruce; Mosley-Thompson, Ellen; Leventer, Amy; Vernet, Maria; Smith, Craig; Thompson, Lonnie G.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "MGDS", "repositories": "AMGRF; MGDS; R2R; USAP-DC", "science_programs": "LARISSA", "south": -67.8, "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "uid": "p0000101", "west": -68.0}, {"awards": "1143836 Leventer, Amy; 1430550 Domack, Eugene; 1143833 Orsi, Alejandro; 1143834 Huber, Bruce", "bounds_geometry": "POLYGON((116 -65.2,116.5 -65.2,117 -65.2,117.5 -65.2,118 -65.2,118.5 -65.2,119 -65.2,119.5 -65.2,120 -65.2,120.5 -65.2,121 -65.2,121 -65.38,121 -65.56,121 -65.74,121 -65.92,121 -66.1,121 -66.28,121 -66.46,121 -66.64,121 -66.82,121 -67,120.5 -67,120 -67,119.5 -67,119 -67,118.5 -67,118 -67,117.5 -67,117 -67,116.5 -67,116 -67,116 -66.82,116 -66.64,116 -66.46,116 -66.28,116 -66.1,116 -65.92,116 -65.74,116 -65.56,116 -65.38,116 -65.2))", "dataset_titles": "AU1402 Final UCTD data; AU1402 mooring data; Bottom photos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402 ; NBP1402 diatom data; NBP1402 Final CTD data; NBP1402 Final UCTD data; NBP1402 JPC43 Diatom Data; NBP14-02 JPC-54 and JPC-55 Pollen Assemblage data; NBP14-02 JPC-55 Bulk Sediment Carbon and Nitrogen data; NBP14-02 JPC-55 foraminifer assemblage data; NBP1402 Lowered ADCP data; Near-bottom Videos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402; Sabrina Coast mooring data - sediment trap mooring 2014", "datasets": [{"dataset_uid": "601148", "doi": "10.15784/601148", "keywords": "Antarctica; Au1402; Mooring; NBP1402; Oceans; Ocean Temperature; Physical Oceanography; R/v Aurora Australis; R/v Nathaniel B. Palmer; Sabrina Coast; Salinity; Southern Ocean; Temperature", "people": "Orsi, Alejandro", "repository": "USAP-DC", "science_program": null, "title": "AU1402 mooring data", "url": "https://www.usap-dc.org/view/dataset/601148"}, {"dataset_uid": "601068", "doi": "10.15784/601068", "keywords": "ADCP Acoustic Doppler Current Profiler; Antarctica; NBP1402; Oceans; Physical Oceanography; Sabrina Coast; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "NBP1402 Lowered ADCP data", "url": "https://www.usap-dc.org/view/dataset/601068"}, {"dataset_uid": "601067", "doi": "10.15784/601067", "keywords": "Antarctica; CTD Data; NBP1402; Oceans; Physical Oceanography; Sabrina Coast; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "NBP1402 Final CTD data", "url": "https://www.usap-dc.org/view/dataset/601067"}, {"dataset_uid": "601046", "doi": "10.15784/601046", "keywords": "Antarctica; Biota; Marine Sediments; NBP1402; Oceans; Paleoclimate; Pollen; Sabrina Coast; Sediment Core; Southern Ocean; Totten Glacier", "people": "Shevenell, Amelia; Domack, Eugene Walter; Smith, Catherine", "repository": "USAP-DC", "science_program": null, "title": "NBP14-02 JPC-54 and JPC-55 Pollen Assemblage data", "url": "https://www.usap-dc.org/view/dataset/601046"}, {"dataset_uid": "601440", "doi": "10.15784/601440", "keywords": "Antarctica; Diatom; Holocene; Jumbo Piston Corer; NBP1402; R/v Nathaniel B. Palmer; Sabrina Coast; Sediment Core Data; Species Abundance; Totten Glacier", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "NBP1402 JPC43 Diatom Data", "url": "https://www.usap-dc.org/view/dataset/601440"}, {"dataset_uid": "601044", "doi": "10.15784/601044", "keywords": "Antarctica; Carbon; Chemistry:sediment; Chemistry:Sediment; Geochemistry; Marine Sediments; NBP1402; Nitrogen; Oceans; Sabrina Coast; Sediment Core; Southern Ocean; Totten Glacier", "people": "Shevenell, Amelia; Smith, Catherine; Domack, Eugene Walter", "repository": "USAP-DC", "science_program": null, "title": "NBP14-02 JPC-55 Bulk Sediment Carbon and Nitrogen data", "url": "https://www.usap-dc.org/view/dataset/601044"}, {"dataset_uid": "601312", "doi": null, "keywords": "Antarctica; Benthic Images; Camera; East Antarctica; Marine Geoscience; NBP1402; Photo/video; Photo/Video; R/v Nathaniel B. Palmer; Sabrina Coast; Totten Glacier; Video Data; Yoyo Camera", "people": "Domack, Eugene Walter; Shevenell, Amelia; Orsi, Alejandro; Huber, Bruce; Gulick, Sean; Blankenship, Donald D.; Post, Alexandra; Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Near-bottom Videos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402", "url": "https://www.usap-dc.org/view/dataset/601312"}, {"dataset_uid": "601310", "doi": null, "keywords": "Antarctica; Benthic Images; Benthos; East Antarctica; Marine Geoscience; NBP1402; Photo; Photo/video; Photo/Video; R/v Nathaniel B. Palmer; Totten Glacier; Yoyo Camera", "people": "Gulick, Sean; Orsi, Alejandro; Domack, Eugene Walter; Post, Alexandra; Huber, Bruce; Shevenell, Amelia; Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Bottom photos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402 ", "url": "https://www.usap-dc.org/view/dataset/601310"}, {"dataset_uid": "601258", "doi": "10.15784/601258", "keywords": "Antarctica; Diatom; NBP1402; Totten Glacier", "people": "Leventer, Amy; NBP1402 science party", "repository": "USAP-DC", "science_program": null, "title": "NBP1402 diatom data", "url": "https://www.usap-dc.org/view/dataset/601258"}, {"dataset_uid": "601146", "doi": "10.15784/601146", "keywords": "Antarctica; CTD Data; NBP1402; Oceans; Ocean Temperature; Physical Oceanography; R/v Nathaniel B. Palmer; Sabrina Coast; Salinity; Southern Ocean; Temperature", "people": "Orsi, Alejandro", "repository": "USAP-DC", "science_program": null, "title": "NBP1402 Final UCTD data", "url": "https://www.usap-dc.org/view/dataset/601146"}, {"dataset_uid": "601147", "doi": "10.15784/601147", "keywords": "Antarctica; CTD Data; NBP1402; Ocean Temperature; Physical Oceanography; Sabrina Coast; Salinity; Southern Ocean; Temperature; Underway CTD", "people": "Orsi, Alejandro", "repository": "USAP-DC", "science_program": null, "title": "AU1402 Final UCTD data", "url": "https://www.usap-dc.org/view/dataset/601147"}, {"dataset_uid": "601042", "doi": "10.15784/601042", "keywords": "Antarctica; Biota; Continental Margin; Foraminifera; NBP1402; Oceans; Paleoclimate; Sabrina Coast; Sample/collection Description; Sample/Collection Description; Southern Ocean; Totten Glacier", "people": "Shevenell, Amelia; Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "NBP14-02 JPC-55 foraminifer assemblage data", "url": "https://www.usap-dc.org/view/dataset/601042"}, {"dataset_uid": "601069", "doi": "10.15784/601069", "keywords": "Antarctica; Mooring; NBP1402; Oceans; Physical Oceanography; Sabrina Coast; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Sabrina Coast mooring data - sediment trap mooring 2014", "url": "https://www.usap-dc.org/view/dataset/601069"}], "date_created": "Fri, 26 Jan 2018 00:00:00 GMT", "description": "This project will investigate the marine component of the Totten Glacier and Moscow University Ice Shelf, East Antarctica. This system is of critical importance because it drains one-eighth of the East Antarctic Ice Sheet and contains a volume equivalent to nearly 7 meters of potential sea level rise, greater than the entire West Antarctic Ice Sheet. This nearly completely unexplored region is the single largest and least understood marine glacial system that is potentially unstable. Despite intense scrutiny of marine based systems in the West Antarctic Ice Sheet, little is known about the Totten Glacier system. This study will add substantially to the meager oceanographic and marine geology and geophysics data available in this region, and will significantly advance understanding of this poorly understood glacial system and its potentially sensitive response to environmental change.\u003cbr/\u003e\u003cbr/\u003eIndependent, space-based platforms indicate accelerating mass loss of the Totten system. Recent aerogeophysical surveys of the Aurora Subglacial Basin, which contains the deepest ice in Antarctica and drains into the Totten system, have provided the subglacial context for measured surface changes and show that the Totten Glacier has been the most significant drainage pathway for at least two previous ice flow regimes. However, the offshore context is far less understood. Limited physical oceanographic data from the nearby shelf/slope break indicate the presence of Modified Circumpolar Deep Water within a thick bottom layer at the mouth of a trough with apparent access to Totten Glacier, suggesting the possibility of sub-glacial bottom inflow of relatively warm water, a process considered to be responsible for West Antarctic Ice Sheet grounding line retreat. This project will conduct a ship-based marine geologic and geophysical survey of the region, combined with a physical oceanographic study, in order to evaluate both the recent and longer-term behavior of the glacial system and its relationship to the adjacent oceanographic system. This endeavor will complement studies of other Antarctic ice shelves, oceanographic studies near the Antarctic Peninsula, and ongoing development of ice sheet and other ocean models.", "east": 121.0, "geometry": "POINT(118.5 -66.1)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD", "is_usap_dc": true, "keywords": "Totten Glacier; NBP1402; Sabrina Coast; LABORATORY; Diatom; R/V NBP; Amd/Us; Bottom Photos; R/V AA; Not provided; USAP-DC; AMD; USA/NSF", "locations": "Sabrina Coast; Totten Glacier", "north": -65.2, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Orsi, Alejandro; Huber, Bruce; Leventer, Amy; Domack, Eugene Walter", "platforms": "Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V AA; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "uid": "p0000008", "west": 116.0}, {"awards": "1443474 Jenkins, Bethany", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1608", "datasets": [{"dataset_uid": "002664", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1608", "url": "https://www.rvdata.us/search/cruise/NBP1608"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "This project focuses on an important group of photosynthetic algae in the Southern Ocean (SO), diatoms, and the roles associated bacterial communities play in modulating their growth. Diatom growth fuels the SO food web and balances atmospheric carbon dioxide by sequestering the carbon used for growth to the deep ocean on long time scales as cells sink below the surface. The diatom growth is limited by the available iron in the seawater, most of which is not freely available to the diatoms but instead is tightly bound to other compounds. The nature of these compounds and how phytoplankton acquire iron from them is critical to understanding productivity in this region and globally. The investigators will conduct experiments to characterize the relationship between diatoms, their associated bacteria, and iron in open ocean and inshore waters. Experiments will involve supplying nutrients at varying nutrient ratios to natural phytoplankton assemblages to determine how diatoms and their associated bacteria respond to different conditions. This will provide valuable data that can be used by climate and food web modelers and it will help us better understand the relationship between iron, a key nutrient in the ocean, and the organisms at the base of the food web that use iron for photosynthetic growth and carbon uptake. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project supports early career senior investigators and the training of graduate and undergraduate students as well as outreach activities with middle school Girl Scouts in Rhode Island, inner city middle and high school age girls in Virginia, and middle school girls in Florida.\u003cbr/\u003e\u003cbr/\u003eThe project combines trace metal biogeochemistry, phytoplankton cultivation, and molecular biology to address questions regarding the production of iron-binding compounds and the role of diatom-bacterial interactions in this iron-limited region. Iron is an essential micronutrient for marine phytoplankton. Phytoplankton growth in the SO is limited by a lack of sufficient iron, with important consequences for carbon cycling and climate in this high latitude regime. Some of the major outstanding questions in iron biogeochemistry relate to the organic compounds that bind \u003e99.9% of dissolved iron in surface oceans. The investigators\u0027 prior research in this region suggests that production of strong iron-binding compounds in the SO is linked to diatom blooms in waters with high nitrate to iron ratios. The sources of these compounds are unknown but the investigators hypothesize that they may be from bacteria, which are known to produce such compounds for their own use. The project will test three hypotheses concerning the production of these iron-binding compounds, limitations on the biological availability of iron even if present in high concentrations, and the roles of diatom-associated bacteria in these processes. Results from this project will provide fundamental information about the biogeochemical trigger, and biological sources and function, of natural strong iron-binding compound production in the SO, where iron plays a critical role in phytoplankton productivity, carbon cycling, and climate regulation.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP; NBP1608", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jenkins, Bethany", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Investigating Iron-inding Ligands in Southern Ocean Diatom Communities: The Role of Diatom-Bacteria Associations", "uid": "p0000852", "west": null}, {"awards": "1543245 Rynearson, Tatiana", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP1701; NCBI Popset of 43 Southern Ocean diatom isolates, including accessions ON678208.1 - ON678250.1; Specific growth rate measurements for 43 Southern Ocean diatoms", "datasets": [{"dataset_uid": "001369", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1701"}, {"dataset_uid": "200328", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "NCBI Popset of 43 Southern Ocean diatom isolates, including accessions ON678208.1 - ON678250.1", "url": "https://www.ncbi.nlm.nih.gov/popset/?term=2248543458"}, {"dataset_uid": "601586", "doi": "10.15784/601586", "keywords": "Antarctica; Biota; NBP1701; Phytoplankton; R/v Nathaniel B. Palmer; Specific Growth Rate; Thermal Optimum Temperature", "people": "Bishop, Ian", "repository": "USAP-DC", "science_program": null, "title": "Specific growth rate measurements for 43 Southern Ocean diatoms", "url": "https://www.usap-dc.org/view/dataset/601586"}, {"dataset_uid": "002661", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1701", "url": "https://www.rvdata.us/search/cruise/NBP1701"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "The research will examine how diatoms (an important group of plankton in the Southern Ocean) adapt to environmental change. Diatoms will be sampled from different regions of the Southern Ocean, including the Drake Passage, the Pacific Sector of the Southern Ocean and the Ross Sea and examined to determine the range of genetic variation among diatoms in these regions. Experiments on a range of diatoms will be conducted in home laboratories and will be aimed at measuring shifts in physiological capacities over many generations in response to directional changes in the environment (temperature and pH). The information on the genetic diversity of field populations combined with information on potential rates of adaptability and genome changes will provide insight into ways in which polar marine diatoms populations may respond to environmental changes that may occur in surface oceans in the future or may have occurred during past climate conditions. Such information allows better modeling of biogeochemical cycles in the ocean as well as improves our abilities to interpret records of past ocean conditions. The project will support a doctoral student and a postdoctoral researcher as well as several undergraduate students. These scientists will learn the fundamentals of experimental evolution, a skill set that is being sought in the fields of biology and oceanography. The project also includes a collaboration with the Metcalf Institute for Marine and Environmental Reporting that will design and facilitate a session focused on current research related to evolution and climate change to be held at the annual conference of the National Association of Science Writers (NASW). \u003cbr/\u003e\u003cbr/\u003eBoth physiological and genetic variation are key parameters for understanding evolutionary processes in phytoplankton but they are essentially unknown for Southern Ocean diatoms. The extent to which these two factors determine plasticity and adaptability in field populations and the interaction between them will influence how and whether cold-adapted diatoms can respond to changing environments. This project includes a combination of field work to identify genetic diversity within diatoms using molecular approaches and experiments in the lab to assess the range of physiological variation in contemporary populations of diatoms and evolution experiments in the lab to assess how the combination of genetic diversity and physiological variation influence the evolutionary potential of diatoms under a changing environment. This research will uncover general relationships between physiological variation, genetic diversity, and evolutionary potential that may apply across microbial taxa and geographical regions, substantially improving efforts to predict shifts in marine ecosystems. Results from this study can be integrated into developing models that incorporate evolution to predict ecosystem changes under future climate change scenarios.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; NBP1701; R/V NBP; AMD; USA/NSF; Amd/Us; DIATOMS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rynearson, Tatiana; Bishop, Ian", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "NCBI; R2R; USAP-DC", "science_programs": null, "south": null, "title": "NSFGEO-NERC: Evolutionary Response of Southern Ocean Diatoms to Environmental Change", "uid": "p0000850", "west": null}, {"awards": "1246378 Shevenell, Amelia", "bounds_geometry": "POLYGON((-65.32 -64.15,-65.309 -64.15,-65.298 -64.15,-65.287 -64.15,-65.276 -64.15,-65.265 -64.15,-65.254 -64.15,-65.243 -64.15,-65.232 -64.15,-65.221 -64.15,-65.21 -64.15,-65.21 -64.186,-65.21 -64.222,-65.21 -64.258,-65.21 -64.294,-65.21 -64.33,-65.21 -64.366,-65.21 -64.402,-65.21 -64.438,-65.21 -64.474,-65.21 -64.51,-65.221 -64.51,-65.232 -64.51,-65.243 -64.51,-65.254 -64.51,-65.265 -64.51,-65.276 -64.51,-65.287 -64.51,-65.298 -64.51,-65.309 -64.51,-65.32 -64.51,-65.32 -64.474,-65.32 -64.438,-65.32 -64.402,-65.32 -64.366,-65.32 -64.33,-65.32 -64.294,-65.32 -64.258,-65.32 -64.222,-65.32 -64.186,-65.32 -64.15))", "dataset_titles": "Anvers Trough Foraminifer Stable Isotope data; Geochemical and sedimentologic data from NBP01-01 JPC-34", "datasets": [{"dataset_uid": "601064", "doi": "10.15784/601064", "keywords": "Antarctica; Antarctic Peninsula; Anvers Trough; Chemistry:sediment; Chemistry:Sediment; Foraminifera; Geochemistry; Isotope; LMG1211; LMG1311; Marine Sediments; Oceans; Paleoclimate; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Anvers Trough Foraminifer Stable Isotope data", "url": "https://www.usap-dc.org/view/dataset/601064"}, {"dataset_uid": "601180", "doi": "10.15784/601180", "keywords": "Antarctica; Be-10; Glaciers/ice Sheet; Glaciers/Ice Sheet; Grain Size; Late Quaternary; Magnetic Susceptibility; Mass Spectrometry; NBP0101; Paleoenvironment; Prydz Bay; Radiocarbon; R/v Nathaniel B. Palmer; Sediment; Sediment Core; Sediment Core Data", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Geochemical and sedimentologic data from NBP01-01 JPC-34", "url": "https://www.usap-dc.org/view/dataset/601180"}], "date_created": "Fri, 27 Oct 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eSouthern Ocean processes play an important role in Late Quaternary glacial-interglacial climate change. However, the direct influence of newly upwelled warm nutrient-rich Circumpolar Deep Water on the Antarctic cryosphere remains speculative. The PI proposes to test the hypothesis that Circumpolar Deep Water-derived ocean heat negatively impacts the mass-balance of Antarctica?s ice sheets during deglaciations using precisely dated late Quaternary paleoceanographic studies of Antarctic margin sediments and a suite of geochemical proxies measured on three existing glacial marine sediment cores from the Prydz Channel, Antarctica. Specifically, the PI will use these data to reconstruct the Late Quaternary history of the Lambert Glacier/Amery Ice Shelf system; evaluate the timing, speed, and style of retreat of the Lambert Glacier/Amery Ice Shelf system during the last deglaciation, and to assess the impact of Circumpolar Deep Water intrusions on the Lambert Glacier/Amery Ice Shelf system in the Late Quaternary. Diatom bound radiocarbon and optically stimulated luminescence techniques will be used to obtain precise stratigraphic age control for the Prydz Channel siliceous muddy ooze intervals. In addition, the PI will measure sedimentary 10Be concentrations to determine the origin of the siliceous muddy ooze units and to track past changes in the position of the ice shelf front.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis proposal will support an early career female scientist and will provide professional development and research experiences for women/minority graduate and undergraduate students. The PI will take advantage of USF?s Oceanography Camp for Girls.", "east": -65.21, "geometry": "POINT(-65.265 -64.33)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "Amd/Us; R/V NBP; USAP-DC", "locations": null, "north": -64.15, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Shevenell, Amelia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.51, "title": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica", "uid": "p0000381", "west": -65.32}, {"awards": "1246378 Shevenell, Amelia", "bounds_geometry": "POLYGON((70 -68,70.5 -68,71 -68,71.5 -68,72 -68,72.5 -68,73 -68,73.5 -68,74 -68,74.5 -68,75 -68,75 -68.2,75 -68.4,75 -68.6,75 -68.8,75 -69,75 -69.2,75 -69.4,75 -69.6,75 -69.8,75 -70,74.5 -70,74 -70,73.5 -70,73 -70,72.5 -70,72 -70,71.5 -70,71 -70,70.5 -70,70 -70,70 -69.8,70 -69.6,70 -69.4,70 -69.2,70 -69,70 -68.8,70 -68.6,70 -68.4,70 -68.2,70 -68))", "dataset_titles": "Anvers Trough Foraminifer Stable Isotope data; Geochemical and sedimentologic data from NBP01-01 JPC-34", "datasets": [{"dataset_uid": "601064", "doi": "10.15784/601064", "keywords": "Antarctica; Antarctic Peninsula; Anvers Trough; Chemistry:sediment; Chemistry:Sediment; Foraminifera; Geochemistry; Isotope; LMG1211; LMG1311; Marine Sediments; Oceans; Paleoclimate; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Anvers Trough Foraminifer Stable Isotope data", "url": "https://www.usap-dc.org/view/dataset/601064"}, {"dataset_uid": "601180", "doi": "10.15784/601180", "keywords": "Antarctica; Be-10; Glaciers/ice Sheet; Glaciers/Ice Sheet; Grain Size; Late Quaternary; Magnetic Susceptibility; Mass Spectrometry; NBP0101; Paleoenvironment; Prydz Bay; Radiocarbon; R/v Nathaniel B. Palmer; Sediment; Sediment Core; Sediment Core Data", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": null, "title": "Geochemical and sedimentologic data from NBP01-01 JPC-34", "url": "https://www.usap-dc.org/view/dataset/601180"}], "date_created": "Fri, 27 Oct 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eSouthern Ocean processes play an important role in Late Quaternary glacial-interglacial climate change. However, the direct influence of newly upwelled warm nutrient-rich Circumpolar Deep Water on the Antarctic cryosphere remains speculative. The PI proposes to test the hypothesis that Circumpolar Deep Water-derived ocean heat negatively impacts the mass-balance of Antarctica?s ice sheets during deglaciations using precisely dated late Quaternary paleoceanographic studies of Antarctic margin sediments and a suite of geochemical proxies measured on three existing glacial marine sediment cores from the Prydz Channel, Antarctica. Specifically, the PI will use these data to reconstruct the Late Quaternary history of the Lambert Glacier/Amery Ice Shelf system; evaluate the timing, speed, and style of retreat of the Lambert Glacier/Amery Ice Shelf system during the last deglaciation, and to assess the impact of Circumpolar Deep Water intrusions on the Lambert Glacier/Amery Ice Shelf system in the Late Quaternary. Diatom bound radiocarbon and optically stimulated luminescence techniques will be used to obtain precise stratigraphic age control for the Prydz Channel siliceous muddy ooze intervals. In addition, the PI will measure sedimentary 10Be concentrations to determine the origin of the siliceous muddy ooze units and to track past changes in the position of the ice shelf front.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis proposal will support an early career female scientist and will provide professional development and research experiences for women/minority graduate and undergraduate students. The PI will take advantage of USF?s Oceanography Camp for Girls.", "east": 75.0, "geometry": "POINT(72.5 -69)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "Amd/Us; R/V NBP; USAP-DC", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Shevenell, Amelia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Late Quaternary Evolution of the Lambert Glacier/Amery Ice Shelf System, Prydz Bay, Antarctica", "uid": "p0000381", "west": 70.0}, {"awards": "1142174 Smith, Walker; 1142074 Ballard, Grant", "bounds_geometry": "POLYGON((165.9 -76.9,166.25 -76.9,166.6 -76.9,166.95 -76.9,167.3 -76.9,167.65 -76.9,168 -76.9,168.35 -76.9,168.7 -76.9,169.05 -76.9,169.4 -76.9,169.4 -76.97,169.4 -77.04,169.4 -77.11,169.4 -77.18,169.4 -77.25,169.4 -77.32,169.4 -77.39,169.4 -77.46,169.4 -77.53,169.4 -77.6,169.05 -77.6,168.7 -77.6,168.35 -77.6,168 -77.6,167.65 -77.6,167.3 -77.6,166.95 -77.6,166.6 -77.6,166.25 -77.6,165.9 -77.6,165.9 -77.53,165.9 -77.46,165.9 -77.39,165.9 -77.32,165.9 -77.25,165.9 -77.18,165.9 -77.11,165.9 -77.04,165.9 -76.97,165.9 -76.9))", "dataset_titles": "Access to data; Experimental analyses of phytoplankton temperature response; Glider data from the southern Ross Sea collected from the iRobot Seaglider during the RVIB Nathaniel B. Palmer (AUV-SG-503-2012, NBP1210) cruises in 2012 (Penguin Glider project); Penguin Science file sharing site", "datasets": [{"dataset_uid": "001426", "doi": "", "keywords": null, "people": null, "repository": "CADC", "science_program": null, "title": "Access to data", "url": "http://data.prbo.org/apps/penguinscience/AllData/NSF-ANT-1142074/"}, {"dataset_uid": "002575", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Glider data from the southern Ross Sea collected from the iRobot Seaglider during the RVIB Nathaniel B. Palmer (AUV-SG-503-2012, NBP1210) cruises in 2012 (Penguin Glider project)", "url": "https://www.bco-dmo.org/dataset/568868/data"}, {"dataset_uid": "002740", "doi": null, "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Penguin Science file sharing site", "url": "https://data.pointblue.org/apps/penguin_science/"}, {"dataset_uid": "601135", "doi": "10.15784/601135", "keywords": "Antarctica; Biota; Chlorophyll; Foraminifera; Growth; Phytoplankton; Plankton; Temperature", "people": "Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Experimental analyses of phytoplankton temperature response", "url": "https://www.usap-dc.org/view/dataset/601135"}], "date_created": "Mon, 14 Dec 2015 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe Ross Sea is believed to contributes a huge portion (~1/3) of the primary productivity of the Southern Ocean and is home to a similar large portion of the top predators (e.g. 38% of Adelie, 28% of Emperor penguins) of the Antarctic sea ice ecosystem. The trophic pathways in this system are complex in both space and time. One scenario for the Ross Sea ecosystem is that diatoms are grazed by krill, which are in turn the preferred food of fish, penguins and other predators. Phaeocystis colonies, on the other hand lead to grazing by pteropods and other organisms that are a non-favoured food source for top predators. Remotely sensed chlorophyll, indicating all phytoplankton, is then suggested to be a relatively poor predictor of penguin foraging efforts. This is also consistent with notion that algal species composition is very important to penguin grazing pressure, mediated by krill, and perhaps resulting in selective depletion. \u003cbr/\u003e\u003cbr/\u003eThis collaborative research sets out to use an autonomous glider, equipped with a range of sensors, and informed by satellite chlorophyll imagery to be combined with 3-dimenisonal active penguin tracking to their preferred foraging sites. The effect of localized grazing pressure of krill on the appearance and disappearance of algal blooms will also be followed. Overall the objective of the research is to reconcile and explain several years of the study of the foraging habits and strategies of (top predator) penguins at the Cape Crozier site (Ross Island), with the dynamics of krill and their supporting algal food webs. The use of a glider to answer a primarily ecological questions is subject to moderate to high risk, and is potentially transformative.", "east": 169.4, "geometry": "POINT(167.65 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; USAP-DC", "locations": null, "north": -76.9, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; Ballard, Grant", "platforms": "Not provided", "repo": "CADC", "repositories": "BCO-DMO; CADC; Project website; USAP-DC", "science_programs": null, "south": -77.6, "title": "Collaborative Research: Penguin Foraging Reveals Phytoplankton Spatial Structure in the Ross Sea", "uid": "p0000322", "west": 165.9}, {"awards": "1043690 Scherer, Reed", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "datasets": [{"dataset_uid": "600127", "doi": "10.15784/600127", "keywords": "Antarctica; Biota; Diatom; Marine Sediments; Oceans; Sediment Core; Southern Ocean", "people": "Scherer, Reed Paul; Haji-Sheikh, Michael", "repository": "USAP-DC", "science_program": null, "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "url": "https://www.usap-dc.org/view/dataset/600127"}], "date_created": "Fri, 14 Feb 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eDiatom abundance in sediment cores is typically used as a proxy for paleo primary productivity. This record is complicated by variable preservation, with most loss occurring in the water column via dissolution and zooplankton grazing. This study will investigate preservational biases via a series of controlled experiments to create proxies of original productivity based on morphological changes associated with diatom dissolution and fracture. The PIs will utilize fresh diatoms from culture. Specific objectives include: (1) Linking changes in diatom morphology to availability of dissolved silica and other physical and chemical parameters; (2) Documenting the dissolution process under controlled conditions; (3) Assessment of changes in morphology and diatom surface roughness with increased dissolution; (4) Documenting the physical effects of grazing and fecal pellet formation on diatom fragmentation and dissolution; and (5) Analyzing the impact of diatom dissolution on silica and carbon export. These objectives will be achieved by growing Southern Ocean diatom species in the laboratory under differing physical and chemical conditions; controlled serial dissolution experiments on cultured diatoms; analysis of the dissolution process by imaging frustules under scanning electron microscopy (SEM) and with micro-analysis of surface texture by atomic force microscopy (AFM); making the cultures available to krill and other live zooplankton crustaceans in order to analyze the specific effects of grazing and pelletization on diatom morphology; and comparing experimental results with natural plankton, sediment trap material, and selected Holocene, Pleistocene and Pliocene sediment core material. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis work will contribute to understanding of the use of diatom abundance as an indicator of paleoproductivity. The proposed experiments are multi-disciplinary in nature. Importantly, the project was designed, and the proposal largely written, by a Ph.D. candidate. The research proposed here will lead to peer-reviewed publications and provide a base for future studies over the course of an extremely promising scientific career. The project will also support an undergraduate research student at NIU. The PI is heavily involved in science outreach, including classroom visits, museum events and webinars related to evolution and climate change, and is active with NSF-funded outreach activities linked to the ANDRILL and WISSARD programs. He will continue these efforts with this project.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Haji-Sheikh, Michael; Scherer, Reed Paul", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "uid": "p0000360", "west": -180.0}, {"awards": "9909367 Leventer, Amy", "bounds_geometry": "POLYGON((26.27227 -42.81742,38.414467 -42.81742,50.556664 -42.81742,62.698861 -42.81742,74.841058 -42.81742,86.983255 -42.81742,99.125452 -42.81742,111.267649 -42.81742,123.409846 -42.81742,135.552043 -42.81742,147.69424 -42.81742,147.69424 -45.454494,147.69424 -48.091568,147.69424 -50.728642,147.69424 -53.365716,147.69424 -56.00279,147.69424 -58.639864,147.69424 -61.276938,147.69424 -63.914012,147.69424 -66.551086,147.69424 -69.18816,135.552043 -69.18816,123.409846 -69.18816,111.267649 -69.18816,99.125452 -69.18816,86.983255 -69.18816,74.841058 -69.18816,62.698861 -69.18816,50.556664 -69.18816,38.414467 -69.18816,26.27227 -69.18816,26.27227 -66.551086,26.27227 -63.914012,26.27227 -61.276938,26.27227 -58.639864,26.27227 -56.00279,26.27227 -53.365716,26.27227 -50.728642,26.27227 -48.091568,26.27227 -45.454494,26.27227 -42.81742))", "dataset_titles": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica; NB0101 Expedition Data; Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "datasets": [{"dataset_uid": "001879", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NB0101 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0101"}, {"dataset_uid": "601177", "doi": "10.15784/601177", "keywords": "Antarctica; Biota; Diatom; East Antarctica; Microscopy; NBP0101; Oceans; Paleoceanography; Paleoclimate; R/v Nathaniel B. Palmer; Sediment Corer", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/601177"}, {"dataset_uid": "601307", "doi": null, "keywords": "Antarctica; Biota; Diatom; East Antarctica; Mac. Robertson Shelf; Marine Geoscience; Microscope; NBP0101; Paleoclimate; Piston Corer; R/v Nathaniel B. Palmer; Sediment Core; Species Abundance", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "url": "https://www.usap-dc.org/view/dataset/601307"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a multi-institutional, international (US - Australia) marine geologic and geophysical investigation of Prydz Bay and the MacRobertson Shelf, to be completed during an approximately 60-day cruise aboard the RVIB N.B. Palmer. The primary objective is to develop a record of climate and oceanographic change during the Quaternary, using sediment cores collected via kasten and jumbo piston coring. Core sites will be selected based on seismic profiling (Seabeam 2112 and Bathy2000). Recognition of the central role of the Antarctic Ice Sheet to global oceanic and atmospheric systems is based primarily on data collected along the West Antarctic margin, while similar extensive and high resolution data sets from the much more extensive East Antarctic margin are sparse. Goals of this project include (1) development of a century- to millennial-scale record of Holocene paleoenvironments, and (2) testing of hypotheses concerning the sedimentary record of previous glacial and interglacial events on the shelf, and evaluation of the timing and extent of maximum glaciation along this 500 km stretch of the East Antarctic margin. \u003cbr/\u003e\u003cbr/\u003eHigh-resolution seismic mapping and coring of sediments deposited in inner shelf depressions will be used to reconstruct Holocene paleoenvironments. In similar depositional settings in the Antarctic Peninsula and Ross Sea, sedimentary records demonstrate millennial- and century- scale variability in primary production and sea-ice extent during the Holocene, which have been linked to chronological periodicities in radiocarbon distribution, suggesting the possible role of solar variability in driving some changes in Holocene climate. Similar high-resolution Holocene records from the East Antarctic margin will be used to develop a circum-Antarctic suite of data regarding the response of southern glacial and oceanographic systems to late Quaternary climate change. In addition, these data will help us to evaluate the response of the East Antarctic margin to global warming. \u003cbr/\u003e\u003cbr/\u003eInitial surveys of the Prydz Channel - Amery Depression region reveal sequences deposited during previous Pleistocene interglacials. The upper Holocene and lower (undated) siliceous units can be traced over 15,000 km2 of the Prydz Channel, but more sub-bottom seismic reflection profiling in conjunction with dense coring over this region is needed to define the spatial distribution and extent of the units. Chronological work will determine the timing and duration of previous periods of glacial marine sedimentation on the East Antarctic margin during the late Pleistocene. \u003cbr/\u003e\u003cbr/\u003eAnalyses will focus on detailed sedimentologic, geochemical, micropaleontological, and paleomagnetic techniques. This multi-parameter approach is the most effective way to extract a valuable paleoenvironmental signal in these glacial marine sediments. These results are expected to lead to a significant advance in understanding of the behavior of the Antarctic ice-sheet and ocean system in the recent geologic past.\u003cbr/\u003e\u003cbr/\u003eThe combination of investigators, all with many years of experience working in high latitude marine settings, will provide an effective team to complete the project. University and College faculty (Principal Investigators on this project) will supervise a combination of undergraduate and post-graduate students involved in all stages of the project so that educational objectives will be met in tandem with the research goals of the project.", "east": 147.69424, "geometry": "POINT(86.983255 -56.00279)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "R/V NBP; USAP-DC", "locations": null, "north": -42.81742, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Leventer, Amy", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -69.18816, "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "uid": "p0000609", "west": 26.27227}, {"awards": "0732535 Arrigo, Kevin", "bounds_geometry": "POLYGON((-130 -67,-127.1 -67,-124.2 -67,-121.3 -67,-118.4 -67,-115.5 -67,-112.6 -67,-109.7 -67,-106.8 -67,-103.9 -67,-101 -67,-101 -67.9,-101 -68.8,-101 -69.7,-101 -70.6,-101 -71.5,-101 -72.4,-101 -73.3,-101 -74.2,-101 -75.1,-101 -76,-103.9 -76,-106.8 -76,-109.7 -76,-112.6 -76,-115.5 -76,-118.4 -76,-121.3 -76,-124.2 -76,-127.1 -76,-130 -76,-130 -75.1,-130 -74.2,-130 -73.3,-130 -72.4,-130 -71.5,-130 -70.6,-130 -69.7,-130 -68.8,-130 -67.9,-130 -67))", "dataset_titles": "GEOTRACES International Data Assembly Centre Accession# NIO100280", "datasets": [{"dataset_uid": "000212", "doi": "", "keywords": null, "people": null, "repository": "GEOTRACES", "science_program": null, "title": "GEOTRACES International Data Assembly Centre Accession# NIO100280", "url": "http://www.bodc.ac.uk/geotraces/"}], "date_created": "Thu, 24 Feb 2011 00:00:00 GMT", "description": "IPY: Shedding dynamic light on iron limitation: The interplay of iron\u003cbr/\u003elimitation and dynamic irradiance in governing the phytoplankton\u003cbr/\u003edistribution in the Ross Sea\u003cbr/\u003e\u003cbr/\u003eThe Southern Ocean plays an important role in the global carbon cycle, accounting for approximately 25% of total anthropogenic CO2 uptake by the oceans, mainly via primary production. In the Ross Sea, primary production is dominated by two taxa that are distinct in location and timing. Diatoms dominate in the shallow mixed layer of the continental shelf, whereas the colony forming Phaeocystis antarctica (Prymnesiophyceae) dominate in the more deeply mixed, open regions. Significantly, both groups have vastly different nutrient utilization characteristics, and support very different marine food webs. Their responses to climate change, and the implications for carbon export, are unclear. Previous studies show that light availability and the quality of the light climate (static versus dynamic) play a major role in defining where and when the different phytoplankton taxa bloom. However, iron (Fe) limitation of the algal communities in both the sub-Arctic and the Southern Ocean is now well documented. Moreover, phytoplankton Fe demand varies as a function of irradiance. The main hypothesis of the proposed research is: The interaction between Fe limitation and dynamic irradiance governs phytoplankton distributions in the Ross Sea. Our strategy to test this hypothesis is three-fold: 1) The photoacclimation of the different phytoplankton taxa to different light conditions under Fe limitation will be investigated in experiments in the laboratory under controlled Fe conditions. 2) The photophysiological mechanisms found in these laboratory experiments will then be tested in the field on two cruises with international IPY partners. 3) Finally, data generated during the lab and field parts of the project will be used to parameterize a dynamic light component of the Coupled Ice Atmosphere and Ocean (CIAO) model of the Ross Sea. Using the improved model, we will run future climate scenarios to test the impact of climate change on the phytoplankton community structure, distribution, primary production and carbon export in the Southern Ocean. The proposed research complies with IPY theme\" Understanding Environmental change in Polar Regions\" and includes participation in an international cruise. Detailed model descriptions and all of the results generated from these studies will be made public via a DynaLiFe website. Improving the CIAO model will give us and other IPY partners the opportunity to test the ecological consequences of physiological characteristics observed in Antarctic phytoplankton under current and future climate scenarios. Outreach will include participation in Stanford\u0027s Summer Program for Professional Development for Science Teachers, Stanford\u0027s School of Earth Sciences high school internship program, and development of curriculum for local science training centers, including the Chabot Space and Science Center.", "east": -101.0, "geometry": "POINT(-115.5 -71.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -67.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Arrigo, Kevin", "platforms": "Not provided", "repo": "GEOTRACES", "repositories": "GEOTRACES", "science_programs": null, "south": -76.0, "title": "IPY: Shedding dynamic light on iron limitation: The interplay of iron limitation and dynamic irradiance in governing the phytoplankton distribution in the Ross Sea", "uid": "p0000112", "west": -130.0}, {"awards": "0542456 Caron, David; 0542111 Lonsdale, Darcy", "bounds_geometry": "POLYGON((-179.9999 -43.5663,-143.99993 -43.5663,-107.99996 -43.5663,-71.99999 -43.5663,-36.00002 -43.5663,-0.000050000000016 -43.5663,35.99992 -43.5663,71.99989 -43.5663,107.99986 -43.5663,143.99983 -43.5663,179.9998 -43.5663,179.9998 -46.99537,179.9998 -50.42444,179.9998 -53.85351,179.9998 -57.28258,179.9998 -60.71165,179.9998 -64.14072,179.9998 -67.56979,179.9998 -70.99886,179.9998 -74.42793,179.9998 -77.857,143.99983 -77.857,107.99986 -77.857,71.99989 -77.857,35.99992 -77.857,-0.000049999999987 -77.857,-36.00002 -77.857,-71.99999 -77.857,-107.99996 -77.857,-143.99993 -77.857,-179.9999 -77.857,-179.9999 -74.42793,-179.9999 -70.99886,-179.9999 -67.56979,-179.9999 -64.14072,-179.9999 -60.71165,-179.9999 -57.28258,-179.9999 -53.85351,-179.9999 -50.42444,-179.9999 -46.99537,-179.9999 -43.5663))", "dataset_titles": "Do Crustacean Zooplankton Play a Pivotal Role in Structuring Heterotrophic Plankton Communities in the Ross Sea?; Expedition Data; NBP0802 data; Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "datasets": [{"dataset_uid": "600059", "doi": "10.15784/600059", "keywords": "Antarctica; Biota; Crustacea; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "Lonsdale, Darcy", "repository": "USAP-DC", "science_program": null, "title": "Do Crustacean Zooplankton Play a Pivotal Role in Structuring Heterotrophic Plankton Communities in the Ross Sea?", "url": "https://www.usap-dc.org/view/dataset/600059"}, {"dataset_uid": "000122", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0802 data", "url": "https://www.rvdata.us/search/cruise/NBP0802"}, {"dataset_uid": "001517", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0801"}, {"dataset_uid": "601344", "doi": null, "keywords": "Antarctica; Cape Adare; Mooring; NBP0801; Physical Oceanography; Ross Sea; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "url": "https://www.usap-dc.org/view/dataset/601344"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Recent studies of marine ecosystems show conflicting evidence for trophic cascades, and in particular the relative strength of the crustacean zooplankton-phytoplankton link. The Ross Sea is a natural laboratory for investigating this apparent conflict. It is a site of seasonally high abundances of phytoplankton, characterized by regions of distinct phytoplankton taxa; the southcentral polynya is strongly dominated by the colony-forming prymnesiophyte Phaeocystis antarctica, while coastal regions of this sea are typically dominated by diatoms or flagellate species. Recent studies indicate that, while the south-central polynya exhibits a massive phytoplankton bloom, the poor food quality of P. antarctica for many crustacean zooplankton prevents direct utilization of much of this phytoplankton bloom. Rather, evidence suggests that indirect utilization of this production may be the primary mechanism by which carbon and energy become available to those higher trophic levels. Specifically, we hypothesize that nano and microzooplankton constitute an important food source for crustacean zooplankton (largely copepods and juvenile euphausiids) during the summer period in the Ross Sea where the phytoplankton assemblage is dominated by the prymnesiophyte. In turn, we also hypothesize that predation by copepods (and other Crustacea) controls and structures the species composition of these protistan assemblages. We will occupy stations in the south-central Ross Sea Polynya (RSP) and Terra Nova Bay (TNB) during austral summer to test these hypotheses. We hypothesize that the diatom species that dominate the phytoplankton assemblage in TNB constitute a direct source of nutrition to herbivorous/omnivorous zooplankton (relative to the situation in the south-central RSP). That is, the contribution of heterotrophic protists to crustacean diets will be reduced in TNB. Our research will address fundamental gaps in our knowledge of food web structure and trophic cascades, and provide better understanding of the flow of carbon and energy within the biological community of this perennially cold sea. The PIs will play active roles in public education (K-12) via curriculum development (on Antarctic biology) and teacher trainer activities in the Centers for Ocean Science Education Excellence (COSEE-West), an innovative, NSF-funded program centered at USC and UCLA.", "east": 179.9998, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V NBP", "locations": null, "north": -43.5663, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Lonsdale, Darcy; Caron, Bruce", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.857, "title": "Collaborative Research: Do Crustacean Zooplankton Play a Pivotal Role in Structuring Heterotrophic Plankton Communities in the Ross Sea?", "uid": "p0000520", "west": -179.9999}, {"awards": "9317538 Nelson, David", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9406", "datasets": [{"dataset_uid": "002591", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9406", "url": "https://www.rvdata.us/search/cruise/NBP9406"}, {"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will test the closely related hypotheses that: (1) phytoplankton growth is controlled primarily by the relationship between solar irradiance and mixed-layer depth throughout the spring (2) diatom growth rates are much higher in spring than at any other time of year, in response to the more favorable irradiance/mixing relationships, and (3) persistence of diatom blooms in summer results from the diatoms\u0027 ability to outcompete other groups under the light-limited conditions that develop in turbid, high-biomass waters. These hypotheses will be tested by (1) obtaining the first reliable estimates of the Sverdrup \"critical depth\" in the Antarctic so that the changing relationship between the critical depth and the mixed- layer depth in spring can be defined, and (2) estimating diatom growth rates and the gross and net production attributable to diatoms throughout the spring. The results will provide information critical to an understanding of phytoplankton bloom dynamics in the Ross Sea.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Bloom Dynamics and Food-Web Structure in the Ross Sea: The Irradiance/Mixing Regime and Diatom Growith in Spring", "uid": "p0000810", "west": null}, {"awards": "0087401 Smith, Walker", "bounds_geometry": null, "dataset_titles": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Expedition data of NBP0301B; Expedition data of NBP0305A; Expedition data of NBP0501; Expedition data of NBP0601A; Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "datasets": [{"dataset_uid": "002622", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "601333", "doi": null, "keywords": "Antarctica; Flourometer; Mooring; NBP0601A; Ross Sea; Southern Ocean", "people": "Smith, Walker; Asper, Vernon", "repository": "USAP-DC", "science_program": null, "title": "Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601333"}, {"dataset_uid": "601339", "doi": null, "keywords": "Antarctica; Current Meter; Mooring; NBP0601A; Oceans; Physical Oceanography; Ross Sea; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601339"}, {"dataset_uid": "601341", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Mooring; NBP0601A; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Seawater Measurements; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "url": "https://www.usap-dc.org/view/dataset/601341"}, {"dataset_uid": "002583", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0301B", "url": "https://www.rvdata.us/search/cruise/NBP0301B"}, {"dataset_uid": "002621", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0305A", "url": "https://www.rvdata.us/search/cruise/NBP0305A"}, {"dataset_uid": "002623", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601A", "url": "https://www.rvdata.us/search/cruise/NBP0601A"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "During the past few decades of oceanographic research, it has been recognized that significant variations in biogeochemical processes occur among years. Interannual variations in the Southern Ocean are known to occur in ice extent and concentration, in the composition of herbivore communities, and in bird and marine mammal distributions and reproductive success. However, little is known about the interannual variations in production of phytoplankton or the role that these variations play in the food web. This project will collect time series data on the seasonal production of phytoplankton in the southern Ross Sea, Antarctica. Furthermore, it will assess the interannual variations of the production of the two major functional groups of the system, diatoms and Phaeocystis Antarctica, a colonial haptophyte. The Ross Sea provides a unique setting for this type of investigation for a number of reasons. For example, a de facto time-series has already been initiated in the Ross Sea through the concentration of a number of programs in the past ten years. It also is well known that the species diversity is reduced relative to other systems and its seasonal production is as great as anywhere in the Antarctic. Most importantly, seasonal production of both the total phytoplankton community (as well as its two functional groups) can be estimated from late summer nutrient profiles. The project will involve short cruises on the US Coast Guard ice breakers in the southern Ross Sea that will allow the collection of water column nutrient and particulate after data at specific locations in the late summer of each of five years. Additionally, two moorings with in situ nitrate analyzers moored at fifteen will be deployed, thus collecting for the first time in the in the Antarctic a time-series of euphotic zone nutrient concentrations over the entire growing season. All nutrient data will be used to calculate seasonal production for each year in the southern Ross Sea and compared to previously collected information, thereby providing an assessment of interannual variations in net community production. Particulate matter data will allow us to estimate the amount of export from the surface layer by late summer, and therefore calculate the interannual variability of this ecosystem process. Interannual variations of seasonal production (and of the major taxa of producers) are a potentially significant feature in the growth and survival of higher trophic levels within the food web of the Ross Sea. They are also important in order to understand the natural variability in biogeochemical processes of the region. Because polar regions such as the Ross Sea are predicted to be impacted by future climate change, biological changes are also anticipated. Placing these changes in the context of natural variability is an essential element of understanding and predicting such alterations. This research thus seeks to quantify the natural variability of an Antarctic coastal system, and ultimately understand its causes and impacts on food webs and biogeochemical cycles of the Ross Sea.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "Ross Sea; AMD; USAP-DC; Amd/Us; USA/NSF; R/V NBP", "locations": "Ross Sea", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Interannual Variability in the Antarctic-Ross Sea (IVARS): Nutrients and Seasonal Production", "uid": "p0000803", "west": null}, {"awards": "0338164 Sedwick, Peter", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0601", "datasets": [{"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}, {"dataset_uid": "002619", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601", "url": "https://www.rvdata.us/search/cruise/NBP0601"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Interactive Effects of Iron, Light and CO2 on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000831", "west": null}, {"awards": "9317587 Smith, Walker", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9406", "datasets": [{"dataset_uid": "002582", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9406", "url": "https://www.rvdata.us/search/cruise/NBP9406"}, {"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will conduct a set of process-oriented experiments designed to elucidate the controls of phytoplankton productivity, growth and accumulation as well as the mechanisms which control bacterial abundance and productivity in Antarctic waters. Specifically, the relative photosynthetic and nutrient (nitrate, ammonium) characteristics of diatom- vs. Phaeocystis- dominated assemblages will be examined to test if Phaeocystis simply grows faster under spring conditions in the Ross Sea. Phytoplankton and bacterial biomass, productivity and their interactions will be measured to elucidate the complex physical-chemical-biological interactions which occur. Substantial understanding of the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions will result from this research. Finally, because the Antarctic is the ocean\u0027s largest high-nutrient, low biomass system, and hence has the greatest potential for sequestering carbon dioxide, knowledge of the dynamics of the Ross Sea phytoplankton will also increase our understanding of the carbo n cycle of the Southern Ocean.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Bloom Dynamics and Food Web Structure in the Ross Sea: Primary Productivity, New Production and Bacterial Growth", "uid": "p0000802", "west": null}, {"awards": "0338157 Smith, Walker; 0741411 Hutchins, David; 0338097 DiTullio, Giacomo; 0338350 Dunbar, Robert; 0127037 Neale, Patrick", "bounds_geometry": "POLYGON((173.31833 -46.5719,173.757539 -46.5719,174.196748 -46.5719,174.635957 -46.5719,175.075166 -46.5719,175.514375 -46.5719,175.953584 -46.5719,176.392793 -46.5719,176.832002 -46.5719,177.271211 -46.5719,177.71042 -46.5719,177.71042 -48.759516,177.71042 -50.947132,177.71042 -53.134748,177.71042 -55.322364,177.71042 -57.50998,177.71042 -59.697596,177.71042 -61.885212,177.71042 -64.072828,177.71042 -66.260444,177.71042 -68.44806,177.271211 -68.44806,176.832002 -68.44806,176.392793 -68.44806,175.953584 -68.44806,175.514375 -68.44806,175.075166 -68.44806,174.635957 -68.44806,174.196748 -68.44806,173.757539 -68.44806,173.31833 -68.44806,173.31833 -66.260444,173.31833 -64.072828,173.31833 -61.885212,173.31833 -59.697596,173.31833 -57.50998,173.31833 -55.322364,173.31833 -53.134748,173.31833 -50.947132,173.31833 -48.759516,173.31833 -46.5719))", "dataset_titles": "Expedition Data; Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea; Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601", "datasets": [{"dataset_uid": "001687", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0305"}, {"dataset_uid": "601340", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Geochemistry; NBP0601; Niskin Bottle; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Water Measurements", "people": "DiTullio, Giacomo; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601", "url": "https://www.usap-dc.org/view/dataset/601340"}, {"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}, {"dataset_uid": "600036", "doi": "10.15784/600036", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; Diatom; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "DiTullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600036"}, {"dataset_uid": "001545", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0608"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.", "east": 177.71042, "geometry": "POINT(175.514375 -57.50998)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF", "is_usap_dc": true, "keywords": "B-15J; OCEAN PLATFORMS; FIELD SURVEYS; R/V NBP", "locations": "B-15J", "north": -46.5719, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo; Smith, Walker; Dryer, Jennifer; Neale, Patrick", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; WATER-BASED PLATFORMS \u003e FIXED PLATFORMS \u003e SURFACE \u003e OCEAN PLATFORMS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -68.44806, "title": "Collaborative Research: Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000540", "west": 173.31833}, {"awards": "0440711 Marchant, David", "bounds_geometry": "POLYGON((160 -76.5,160.45 -76.5,160.9 -76.5,161.35 -76.5,161.8 -76.5,162.25 -76.5,162.7 -76.5,163.15 -76.5,163.6 -76.5,164.05 -76.5,164.5 -76.5,164.5 -76.7,164.5 -76.9,164.5 -77.1,164.5 -77.3,164.5 -77.5,164.5 -77.7,164.5 -77.9,164.5 -78.1,164.5 -78.3,164.5 -78.5,164.05 -78.5,163.6 -78.5,163.15 -78.5,162.7 -78.5,162.25 -78.5,161.8 -78.5,161.35 -78.5,160.9 -78.5,160.45 -78.5,160 -78.5,160 -78.3,160 -78.1,160 -77.9,160 -77.7,160 -77.5,160 -77.3,160 -77.1,160 -76.9,160 -76.7,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 01 Jul 2009 00:00:00 GMT", "description": "This project studies ancient lake deposits from the western Dry Valleys of Antarctica. These deposits are particularly exciting because they preserve flora and fauna over seven million years in age that represent the last vestiges of ecosystems that dominated this area before formation of the modern East Antarctic ice sheet. Their unique nature offers a chance to bridge modern and ancient ecology. Formed along the margin of ancient alpine glaciers, these deposits contain layers of silt, clay, and volcanic ash; as well as freeze-dried remnants of mosses, insects, and diatoms. Geological and biological analyses provide a view of the ecological and environmental conditions during mid-to-late Miocene--seven to seventeen million years ago--which spans the critical period when the East Antarctic ice sheet transitioned to its present stable form. The results place the modern lakes of the Dry Valleys into a long-term evolutionary framework, and allow for correlation and dating comparisons with other fossil-rich deposits from the Transantarctic Mountains. Chemical fingerprinting and dating of volcanic glass shards will also help date fossil- and ash-bearing horizons in nearby marine cores, such as those to be collected under the ANDRILL program. \u003cbr/\u003e\u003cbr/\u003eThe broader impacts are education at the postdoctoral, graduate, and undergraduate levels; and collaboration between a research institution and primarily undergraduate institution. The work also improves our understanding of global climate change during a critical period in the Earth\u0027s history.", "east": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": false, "keywords": "Paleoclimate; Not provided; Lacustrine; Tundra; Middle Miocene; Mcmurdo Dry Valleys; Vegetation; Fossil; Antarctica", "locations": "Antarctica; Mcmurdo Dry Valleys", "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marchant, David", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.5, "title": "Collaborative Research: Deducing Late Neogene Antarctic Climate from Fossil-Rich Lacustrine Sediments in the Dry Valleys", "uid": "p0000186", "west": 160.0}, {"awards": "0739693 Ashworth, Allan; 0739700 Marchant, David", "bounds_geometry": "POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))", "dataset_titles": "Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "datasets": [{"dataset_uid": "600081", "doi": "10.15784/600081", "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; GPS; Solid Earth", "people": "Lewis, Adam; Ashworth, Allan", "repository": "USAP-DC", "science_program": null, "title": "Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/600081"}], "date_created": "Mon, 22 Jun 2009 00:00:00 GMT", "description": "This project studies the last vestiges of life in Antarctica from exceptionally well-preserved fossils of tundra life--mosses, diatoms, ostracods, Nothofagus leaves, wood, and insect remains recently discovered in ancient lake sediments from the McMurdo Dry Valleys. The area will be studied by an interdisciplinary team to elucidate information about climate and biogeography. These deposits offer unique and direct information about the characteristics of Antarctica during a key period in its history, the time when it was freezing. This information is critical for correlation with indirect proxies, such as though obtained from drill cores, for climate and state of the ice sheet. The results will also help understand the origin and migration of similar organisms found in South America, India and Australia.\u003cbr/\u003e\u003cbr/\u003eIn terms of broader impacts, this project supports an early career researcher, undergraduate and graduate student research, various forms of outreach to K12 students, and extensive international collaboration. The work also has societal relevance in that the outcomes will offer direct constraints on Antarctica\u0027s ice sheet during a time with atmospheric CO2 contents similar to those of the earth in the coming centuries, and thus may help predictive models of sea level rise.", "east": 162.0, "geometry": "POINT(161 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; Antarctica; Vegetation; Paleoclimate; Middle Miocene; Tundra; Bu/es Data Repository; Mcmurdo Dry Valleys; Lacustrine; Fossil", "locations": "Antarctica; Mcmurdo Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Ashworth, Allan; Lewis, Adam", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "uid": "p0000188", "west": 160.0}, {"awards": "0453680 Sigman, Daniel", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Robinson et al. 2004 Southern Ocean Diatom-bound Nitrogen and d15N Data", "datasets": [{"dataset_uid": "000119", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Robinson et al. 2004 Southern Ocean Diatom-bound Nitrogen and d15N Data", "url": "https://www.ncdc.noaa.gov/paleo-search/study/8751"}], "date_created": "Wed, 20 May 2009 00:00:00 GMT", "description": "The Southern Ocean may play a central role in causing ice ages and general global climate change. This work will reveal key characteristics of the glacial ocean, and may explain the cause of glacial/interglacial cycles by measuring the abundances of certain isotopes of nitrogen found in fossil diatoms from Antarctic marine sediments. Diatom-bound N is a potentially important recorder of nutrient utilization. The Southern Ocean\u0027s nutrient status, productivity and circulation may be central to setting global atmospheric CO2 contents and other aspects of climate. Previous attempts to make these measurements have yielded ambiguous results. This project includes both technique development and analyses, including measurements on diatoms from both sediment traps and culture experiments. With regard to broader impacts, this grant is focused around the education and academic development of a graduate student, by coupling their research with mentorship of an undergraduate researcher", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sigman, Daniel", "platforms": "Not provided", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -90.0, "title": "Application of a New Method for Isotopic Analysis of Diatom Microfossil-bound Nitrogen", "uid": "p0000550", "west": -180.0}, {"awards": "0230268 Anderson, Robert", "bounds_geometry": "POLYGON((-180 -50,-169 -50,-158 -50,-147 -50,-136 -50,-125 -50,-114 -50,-103 -50,-92 -50,-81 -50,-70 -50,-70 -51.5,-70 -53,-70 -54.5,-70 -56,-70 -57.5,-70 -59,-70 -60.5,-70 -62,-70 -63.5,-70 -65,-81 -65,-92 -65,-103 -65,-114 -65,-125 -65,-136 -65,-147 -65,-158 -65,-169 -65,180 -65,177 -65,174 -65,171 -65,168 -65,165 -65,162 -65,159 -65,156 -65,153 -65,150 -65,150 -63.5,150 -62,150 -60.5,150 -59,150 -57.5,150 -56,150 -54.5,150 -53,150 -51.5,150 -50,153 -50,156 -50,159 -50,162 -50,165 -50,168 -50,171 -50,174 -50,177 -50,-180 -50))", "dataset_titles": "Southern Ocean Deglacial Opal, Radionuclide, and Diatom Upwelling Data", "datasets": [{"dataset_uid": "000199", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Southern Ocean Deglacial Opal, Radionuclide, and Diatom Upwelling Data", "url": "https://www.ncdc.noaa.gov/paleo/study/8439"}], "date_created": "Mon, 12 Jan 2009 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the \"Silicic Acid Leakage Hypothesis\" as it relates to global carbon dioxide fluctuations during glacial-interglacial cycles.\u003cbr/\u003e\u003cbr/\u003eIntellectual Merit\u003cbr/\u003eThis project will evaluate the burial rate of biogenic opal in the Pacific sector of the Southern Ocean, both during the Last Glacial Maximum (LGM) and during the Holocene, as a critical test of the \"Silicic Acid Leakage Hypothesis\". \u003cbr/\u003e\u003cbr/\u003eThe \"Silicic Acid Leakage Hypothesis\" has been proposed recently to explain the glacial reduction in the carbon dioxide content of the atmosphere that has been reconstructed from Antarctic ice cores. Vast amounts of dissolved Si (silicic acid) are supplied to surface waters of the Southern Ocean by wind-driven upwelling of deep waters. Today, that dissolved Si is consumed almost quantitatively by diatoms who form skeletal structures composed of biogenic opal (a mineral form of silicon). According to the \"Silicic Acid Leakage Hypothesis\", environmental conditions in the Southern Ocean during glacial periods were unfavorable for diatom growth, leading to reduced (compared to interglacials) efficiency of dissolved Si utilization. Dissolved Si that was not consumed biologically in the glacial Southern ocean was then exported to the tropics in waters that sink in winter to depths of a few hundred meters along the northern fringes of the Antarctic Circumpolar Current, and return some decades later to the sunlit surface in tropical regions of wind-driven upwelling. \u003cbr/\u003e\u003cbr/\u003eAn increase in the amount of dissolved Si that \"leaks\" out of the Southern Ocean and later upwells at low latitudes could shift the global average composition of phytoplankton toward a greater abundance of diatoms and fewer CaCO3-secreting taxa (especially coccolithophorids). Consequences of such a taxonomic shift in the ocean\u0027s phytoplankton assemblage include:\u003cbr/\u003e a) an increase in the global average organic carbon/calcium carbonate ratio of particulate biogenic material sinking into the deep sea;\u003cbr/\u003e b) a reduction in the preservation and burial of calcium carbonate in marine sediments;\u003cbr/\u003e c) an increase in ocean alkalinity as a consequence of the first two changes mentioned above, and;\u003cbr/\u003e d) a lowering of atmospheric CO2 concentrations in response to increased alkalinity of ocean waters. \u003cbr/\u003e\u003cbr/\u003eA complete assessment of the Silicic acid leakage hypothesis will require an evaluation of: (1) Si utilization efficiencies using newly-developed stable isotopic techniques; (2) opal burial rates in low-latitude upwelling regions; and (3) opal burial rates in the Southern Ocean. This project addresses the last of these topics. \u003cbr/\u003e\u003cbr/\u003ePrevious work has shown that there was little change in opal burial rate between the LGM and the Holocene in the Atlantic and Indian sectors of the Southern Ocean. Preliminary results (summarized in this proposal) suggest that the Pacific may have been different, however, in that opal burial rates in the Pacific sector seem to have been lower during the LGM than during the Holocene, allowing for the possibility of \"Si leakage\" from this region. However, available results are too sparse to make any quantitative conclusions at this time. For that reason, we propose to make a comprehensive evaluation of opal burial rates in the Pacific sector of the Southern Ocean. \u003cbr/\u003e\u003cbr/\u003eSignificance and Broader Impacts\u003cbr/\u003eDetermining the mechanism(s) by which the ocean has regulated climate-related changes in the CO2 content of the atmosphere has been the focus of a substantial effort by paleoceanographers over the past two decades. The Silicic Acid Leakage Hypothesis is a viable new candidate mechanism that warrants further exploration and testing. Completion of the proposed work will contribute significantly to that effort. \u003cbr/\u003e\u003cbr/\u003eDuring the course of this work, several undergraduates will be exposed to paleoclimate research through their involvement in this project. Burckle and Anderson are both dedicated to the education and training of young scientists, and to the recruitment of women and under-represented minorities. To illustrate, two summer students (undergraduates) worked in Burckle\u0027s lab during the summer of 2002. One was a woman and the other (male) was a member of an under-represented minority. Anderson and Burckle will continue with similar recruitment efforts during the course of the proposed study. A minority student who has expressed an interest in working on this research during the summer of 2003 has already been identified.", "east": -70.0, "geometry": "POINT(-140 -57.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -50.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, Robert; Burckle, Lloyd", "platforms": "Not provided", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -65.0, "title": "Opal Burial in the Pacific Sector of the Southern Ocean: A Test of the \"Silicic Acid Leakage Hypothesis.\"", "uid": "p0000457", "west": 150.0}, {"awards": "0124049 Berger, Glenn", "bounds_geometry": "POLYGON((161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.20000000000002 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.20000000000002 -77.5,163.4 -77.5,163.4 -77.52,163.4 -77.54,163.4 -77.56,163.4 -77.58,163.4 -77.6,163.4 -77.62,163.4 -77.64,163.4 -77.66,163.4 -77.68,163.4 -77.7,163.20000000000002 -77.7,163 -77.7,162.8 -77.7,162.6 -77.7,162.4 -77.7,162.20000000000002 -77.7,162 -77.7,161.8 -77.7,161.6 -77.7,161.4 -77.7,161.4 -77.68,161.4 -77.66,161.4 -77.64,161.4 -77.62,161.4 -77.6,161.4 -77.58,161.4 -77.56,161.4 -77.54,161.4 -77.52,161.4 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 25 Aug 2008 00:00:00 GMT", "description": "0124049\u003cbr/\u003eBerger\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.", "east": 163.4, "geometry": "POINT(162.4 -77.6)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS", "is_usap_dc": false, "keywords": "Stratigraphy; Climate Variability; Shoreline Deposits; Dry Valleys; Antarctic Lake-level; Luminescence Geochronology; Grain Size; Paleoclimate; Antarctica; LABORATORY; Lake Cores", "locations": "Dry Valleys; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Berger, Glenn; Hall, Brenda; Doran, Peter", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -77.7, "title": "Collaborative Research: Millennial Scale Fluctuations of Dry Valleys Lakes: Implications for Regional Climate Variability and the Interhemispheric (a)Synchrony of Climate Change", "uid": "p0000219", "west": 161.4}, {"awards": "0338163 Leventer, Amy; 0338142 Domack, Eugene; 0338220 Ishman, Scott", "bounds_geometry": "POLYGON((-63 -62,-62.3 -62,-61.6 -62,-60.9 -62,-60.2 -62,-59.5 -62,-58.8 -62,-58.1 -62,-57.4 -62,-56.7 -62,-56 -62,-56 -62.5,-56 -63,-56 -63.5,-56 -64,-56 -64.5,-56 -65,-56 -65.5,-56 -66,-56 -66.5,-56 -67,-56.7 -67,-57.4 -67,-58.1 -67,-58.8 -67,-59.5 -67,-60.2 -67,-60.9 -67,-61.6 -67,-62.3 -67,-63 -67,-63 -66.5,-63 -66,-63 -65.5,-63 -65,-63 -64.5,-63 -64,-63 -63.5,-63 -63,-63 -62.5,-63 -62))", "dataset_titles": "Expedition Data; Expedition data of LMG0404; NBP0603 - Expedition Data; NBP0603 - Paleohistory of the Larsen Ice Shelf System", "datasets": [{"dataset_uid": "002710", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0404", "url": "https://www.rvdata.us/search/cruise/LMG0404"}, {"dataset_uid": "001610", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0502"}, {"dataset_uid": "600027", "doi": "10.15784/600027", "keywords": "ADCP Acoustic Doppler Current Profiler; Antarctic Peninsula; Biota; Diatom; Electromagnetic Data; Flask Glacier; Foehn Winds; Larsen Ice Shelf; Marine Sediments; NBP0603; Oceans; Physical Ice Properties; R/v Nathaniel B. Palmer; Scar Inlet; Southern Ocean", "people": "Domack, Eugene Walter", "repository": "USAP-DC", "science_program": null, "title": "NBP0603 - Paleohistory of the Larsen Ice Shelf System", "url": "https://www.usap-dc.org/view/dataset/600027"}, {"dataset_uid": "000236", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0603 - Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0603"}], "date_created": "Wed, 11 Jun 2008 00:00:00 GMT", "description": "The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990\u0027s. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica\u0027s glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth\u0027s magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.", "east": -56.0, "geometry": "POINT(-59.5 -64.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERAS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "R/V LMG; R/V NBP; Not provided", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Ishman, Scott; Leventer, Amy; Domack, Eugene Walter", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Paleohistory of the Larsen Ice Shelf System: Phase II", "uid": "p0000215", "west": -63.0}, {"awards": "0230469 Wise, Sherwood", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 31 Jul 2007 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports the development of a standardized diatom image catalog or database. Diatoms are considered by many to be the most important microfossil group used today in the study of Antarctic Cenozoic marine deposits south of the Polar Front, from the near shore to deep sea. These microfossils, with walls of silica called frustules, are produced by single-celled plants (algae of the Class Bacillariophyceae) in a great variety of forms. Consequently, they have great biostratigraphic importance in the Southern Ocean and elsewhere for determining the age of marine sediments. Also, paleoclimatic and paleoceanographic studies increasingly rely on fossil diatom data. Changing biogeographic distributions of given taxa indicate shifting paleoecological conditions and provide evidence of the surface productivity and temperatures of ancient oceans. The generality of conclusions, though, is limited by variation in species concepts among workers. The broad research community relies, directly or indirectly, on the accurate identification of diatom species. Current technology can be used to greatly improve upon the standard references that have been used in making these identifications.\u003cbr/\u003e\u003cbr/\u003eThis project will develop an interactive digital-image catalog of modern and Cenozoic fossil diatoms of the Southern Ocean called \"DiatomWare\" for use by specialists and educators as an aid in rapid, accurate, and consistent species identification. As such, this will be a researcher\u0027s resource. It will be especially useful where it is not possible to maintain standard library resources such as onboard research vessels or at remote stations such as McMurdo Station. Major Antarctic geological drilling initiatives such as the new SHALDRIL project and the pending ANDRILL project will benefit from this product because they will rely heavily on diatom biostratigraphy to achieve their research objectives. The DiatomWare image database will be modeled on NannoWare, which was released in October 2002 on CD-ROM as a publication of the International Nannoplankton Association. BugCam will be adapted and modified as necessary to run the DiatomWare database, which can then be run from desktop or laptop computers. Images and text for the database will be scanned from the literature or captured in digital form from light or scanning electron microscopes.\u003cbr/\u003e\u003cbr/\u003eThe software interface will include a number of data fields that can be accessed by the click of a mouse button. Primary information will be the images and descriptions of the holotypes. In addition, representative images of paratypes or hypotypes will be included whenever possible in plain transmitted, differential interference contrast light and, when available, as drawings and SEM images. Also included will be a 35-word or less English diagnosis (\"mini-description\"), the biostratigraphic range in terms of zones and linear time, bibliographic references, lists of species considered junior synonyms, and similar species. The list of similar species will be cross-referenced with their respective image files to enable quick access for direct visual comparison on the viewing screen. Multiple images can be brought to the viewing screen simultaneously, and a zoom feature will permit image examination at a wide range of magnifications. Buttons will allow range charts, a bibliography, and key public-domain publications from the literature to be called up from within the program. The DiatomWare/BugCam package will be distributed at a nominal cost through a major nonprofit society via CD-ROM and free to Internet users on the Worldwide Web. Quality control measures will include critical review of the finalized database by a network of qualified specialists. The completed database will include descriptions and images of between 350 and 400 species, including fossil as well as modern forms that have no fossil record.\u003cbr/\u003e\u003cbr/\u003eThe development of the proposed diatom image database will be important to all research fields that depend on accurate biostratigraphic dating and paleoenvironmental interpretation of Antarctic marine sediments and plankton. The database will also serve as a valuable teaching tool for micropaleontology students and their professors, will provide a rapid means of keying down species for micropaleontologists of varying experience and background, and will promote a uniformity of taxonomic concepts since it will be developed and continuously updated with the advice of a community of nannofossil fossil experts. Broad use of the database is anticipated since it will be widely available through the Internet and on CD-ROM for use on personal computers that do not require large amounts of memory, costly specialized programs, or additional hardware.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wise, Sherwood", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "DiatomWare: An Interactive Digital Image Catalog for Antarctic Cenozoic Diatoms", "uid": "p0000062", "west": null}, {"awards": "0538475 Bart, Philip", "bounds_geometry": "POLYGON((-180 -75,-178 -75,-176 -75,-174 -75,-172 -75,-170 -75,-168 -75,-166 -75,-164 -75,-162 -75,-160 -75,-160 -75.3,-160 -75.6,-160 -75.9,-160 -76.2,-160 -76.5,-160 -76.8,-160 -77.1,-160 -77.4,-160 -77.7,-160 -78,-162 -78,-164 -78,-166 -78,-168 -78,-170 -78,-172 -78,-174 -78,-176 -78,-178 -78,-180 -78,-180 -77.7,-180 -77.4,-180 -77.1,-180 -76.8,-180 -76.5,-180 -76.2,-180 -75.9,-180 -75.6,-180 -75.3,-180 -75))", "dataset_titles": "NBP0802 and NBP0803 Sediment samples (full data link not provided); NBP0802 data; NBP0803 data", "datasets": [{"dataset_uid": "000123", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0803 data", "url": "https://www.rvdata.us/search/cruise/NBP0803"}, {"dataset_uid": "000138", "doi": "", "keywords": null, "people": null, "repository": "AMGRF", "science_program": null, "title": "NBP0802 and NBP0803 Sediment samples (full data link not provided)", "url": "http://www.arf.fsu.edu/"}, {"dataset_uid": "000122", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP0802 data", "url": "https://www.rvdata.us/search/cruise/NBP0802"}], "date_created": "Thu, 29 Mar 2007 00:00:00 GMT", "description": "This project determines the recent history of the West Antarctic Ice Sheet (WAIS) through a multidisciplinary study of the seabed in the Ross Sea of Antarctica. WAIS is perhaps the world\u0027s most critical ice sheet to sea level rise dut to near-future global warming. its history has been a key focus for the past decade, but there are significant questions as to whether WAIS was stable during the last glacial maximum--about 20,000 years ago--or undergoing advance and retreat. This project studies grounding zone translantions in Eastern Basin to constrain WAIS movements using a multidisciplinary approach that integrates multibeam bathymetry, seismic stratigraphy, sedimentology, diatom biostratigraphy, radiocarbon dating, 10Be concentration analyses, and numerical modeling.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts include improving society\u0027s understanding of sea level rise linked to global warming; postdoctoral, graduate, and undergraduate education; and expanding the participation of groups underrepresented in Earth sciences through links with LSU\u0027s Geoscience Alliance to Encourage Minority Participation.", "east": -160.0, "geometry": "POINT(-170 -76.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e SEISMIC REFLECTION PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e WATERGUNS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES", "is_usap_dc": true, "keywords": "Ross Sea; R/V NBP; Ice Sheet; Last Glacial Maximum; Seismic Stratigraphy", "locations": "Ross Sea", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Bart, Philip; Tomkin, Jonathan", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "AMGRF; R2R", "science_programs": null, "south": -78.0, "title": "WAIS grounding-zone migrations in Eastern Basin, Ross Sea and the LGM dilemma: New strategies to resolve the style and timing of outer continental shelf grounding events", "uid": "p0000539", "west": -180.0}]

View results on map Help on results map