[{"awards": "0538657 Severinghaus, Jeffrey", "bounds_geometry": ["POINT(-112.05 -79.28)"], "date_created": "Fri, 20 Oct 2023 00:00:00 GMT", "description": "Major gas components of air data set, containing d15N, d18O of O2, dO2/N2, and dAr/N2 from the WAIS Divide ice core at high resolution. These data are used to constrain surface temperature, biosphere oxygen cycling, and firn thickness through the past \u003e60 kyr.", "east": -112.05, "geometry": ["POINT(-112.05 -79.28)"], "keywords": "Antarctica; Delta 15N; Delta 18O; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Gas Records; Ice Core Records; Isotope; Nitrogen; Nitrogen Isotopes; Oxygen; Oxygen Isotope; Snow/ice; Snow/Ice; WAIS; WAIS Divide", "locations": "WAIS Divide; Antarctica; WAIS", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Severinghaus, Jeffrey P.", "project_titles": "Nitrogen and Oxygen Gas Isotopes in the WAIS Divide Ice Core as Constraints on Chronology, Temperature, and Accumulation Rate", "projects": [{"proj_uid": "p0000036", "repository": "USAP-DC", "title": "Nitrogen and Oxygen Gas Isotopes in the WAIS Divide Ice Core as Constraints on Chronology, Temperature, and Accumulation Rate"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.28, "title": "d15N and d18O of air in the WAIS Divide ice core", "uid": "601747", "west": -112.05}, {"awards": "1245659 Petrenko, Vasilii; 1245821 Brook, Edward J.; 1246148 Severinghaus, Jeffrey", "bounds_geometry": ["POLYGON((161 -77.7,161.1 -77.7,161.2 -77.7,161.3 -77.7,161.4 -77.7,161.5 -77.7,161.6 -77.7,161.7 -77.7,161.8 -77.7,161.9 -77.7,162 -77.7,162 -77.71000000000001,162 -77.72,162 -77.73,162 -77.74,162 -77.75,162 -77.76,162 -77.77,162 -77.78,162 -77.78999999999999,162 -77.8,161.9 -77.8,161.8 -77.8,161.7 -77.8,161.6 -77.8,161.5 -77.8,161.4 -77.8,161.3 -77.8,161.2 -77.8,161.1 -77.8,161 -77.8,161 -77.78999999999999,161 -77.78,161 -77.77,161 -77.76,161 -77.75,161 -77.74,161 -77.73,161 -77.72,161 -77.71000000000001,161 -77.7))"], "date_created": "Tue, 23 Aug 2022 00:00:00 GMT", "description": "High-precision carbon isotope data (d13C-CO2) show atmospheric CO2 during Marine Isotope Stage 4 (MIS 4, ~70.5-59 ka) was controlled by a succession of millennial-scale processes. Enriched d13C-CO2 during peak glaciation suggests increased ocean carbon storage. Variations in d13C-CO2 in early MIS4 suggest multiple processes were active during CO2 drawdown, potentially including decreased land carbon and decreased Southern Ocean air-sea gas exchange superposed on increased ocean carbon storage. CO2 remained low during MIS 4 while d13C-CO2 fluctuations suggest changes in Southern Ocean and North Atlantic air-sea gas exchange. A 7 ppm increase in CO2 at the onset of Dansgaard-Oeschger event 19 (72.1 ka) and a 22 ppm increase in CO2 during late MIS 4 (Heinrich Stadial 6, ~63.5-60 ka) involved additions of isotopically light carbon to the atmosphere. The terrestrial biosphere and Southern Ocean air-sea gas exchange are possible sources, with the latter event also involving decreased ocean carbon storage.", "east": 162.0, "geometry": ["POINT(161.5 -77.75)"], "keywords": "Antarctica; Taylor Glacier", "locations": "Taylor Glacier; Antarctica", "north": -77.7, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "persons": "Menking, James; Shackleton, Sarah; Bauska, Thomas; Buffen, Aron; Brook, Edward J.; Barker, Stephen; Severinghaus, Jeffrey P.; Dyonisius, Michael; Petrenko, Vasilii; Menking, Andy", "project_titles": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "projects": [{"proj_uid": "p0000283", "repository": "USAP-DC", "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "Taylor Glacier CO2 Isotope Data 74-59 kyr", "uid": "601600", "west": 161.0}, {"awards": "0632399 Jefferies, Stuart", "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))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "The ultimate goal of this project is to determine the structure and dynamics of the Sun\u0027s atmosphere, assess the role of MHD waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun\u0027s atmosphere couples to the solar interior. As the solar atmosphere is \u0027home\u0027 to many of the solar phenomena that can have a direct impact on the biosphere, including flares, coronal mass ejections, and the solar wind, the broader impact of such studies is that they will lead to an improved understanding of the Sun-Earth connection. \nUnder the current award we have developed a suite of instruments that can simultaneously image the line-of-sight Doppler velocity and longitudinal magnetic field at four heights in the solar atmosphere at high temporal cadence. The instruments use magneto-optical filters (see Cacciani, Moretti and Rodgers, Solar Physics 174, p.115, 2004) tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), 770 nm (K) and 1083 nm (He). These lines sample the solar atmosphere from the mid-photosphere to the high-chromosphere. \nA proof-of-concept run was made in the Austral summer of 2007/2008 using the Na and K versions of the instruments. Here we recorded over 40 hours of full-disk, intensity images of the Sun in the red and blue wings of the Na and K Fraunhofer lines, in both right- and left-circularly polarized light. The images were obtained at a rate of one every five seconds with a nominal spatial resolution of 4 arc-seconds. The run started at 09:44 UT on February 2, 2008 and ended at 03:30 UT on February 4, 2008.\nData Quality Assessment:\nThe temperature controls of the instrument housings were unable to fully compensate for the harse Antartic winds encountered during the observing run. This led to large (~15 C) temperature swings which adversely affected the instruments (and thus data quality) in two ways: 1) Crystals of Na and K were deposited on the magneto-optical filter windows leading to \"hot spots\" in the images. These \"hot spots\" come and go with time as the temperature changes. 2) The changing temperature caused the optical rails to contract and expand causing the final images to go in- and out-of-focus, thus reducing the resolution to greater than 4 arc-seconds. Both these effect are worse in the K data.\nDespite these problems, the intensity images can be combined to provide magnetic images that show a very high sensitivity (\u003c 5 Gauss in a 5 second integration).\nData Description:\nThe raw data are stored as a series of 1024x1024x4 FITS images. The format is: blue image (left circulary polarized light), blue image (right circularly polarized light), red image (left circulary polarized light), red image (right circularly polarized light).\nThe naming convention for the images is: Type_Instrument_Day_hour_minutes_seconds\nwhere Type is I (intensity), F (flatfield), D (dark)\n Instrument is 0 (Na), 1 (K)\n Day is the day number from the beginning of the year where January 1 is day 0\nFor example, I_0_32_12_34_40.fits is an intensity image taken with the Na instrument at 12:34.40 UT on February 2, 2008.\nNotes: \n1) The flatfield images were acquired by moving a diffuser in front of the Sun during the integration. The resulting images therefore have to be corrected for residual low-spatial frequencies due to the non-flat nature of the light source.\n2) Each FITS file header contains a variety of information on the observation, e.g.,\nF_CNTO\t: number of summed frames in each 5 second integration (*)\nFPS\t\t: Camera frame rate (Frames Per Second)\nFLIP\t: Rate at which the half-wave rotator (magnetic switch) was switched\nINT_PER\t: Integration time (in seconds)\nMOF\t\t: Temperature of magneto-optical filter cell\nWS\t\t: Temperature of wing selector cell\nTEMP_0\t: Temperature of camera 0\nTEMP_1\t: Temperature of camera 1\nTEMP_2\t: Temperature inside instrument (location 1)\nTEMP_3\t: Temperature of narrowband filter\nTEMP_5\t: Temperature of magnets surrounding MOF cell\nTEMP_6\t: Temperature inside instrument (location 2)\nTEMP_7\t: Temperature of housing for magnetic switch\n(*) This is the frame count for the camera. The number of frames in each image for the two different polarization states, is half this number.\nThe measured temperatures are only coarse measurements.\n3) Due to reflection in the final polarizing beam splitter (which separates the \"red\" and \"blue\" signals into the two cameras), the camera 1 data need to \"reversed\" along the x-axis (i.e. listed as [1024:1] instead of [1:1024])\n4) Line-of-sight velocity and magnetic field images are generated from the observed intensity images. Doppler images as (red-blue)/(red+blue), magnetic images as the difference between the Doppler images\nfor right- and left-circularly polarized light.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cosmos; Satellite Remote Sensing; Sun", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Jefferies, Stuart M.", "project_titles": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "projects": [{"proj_uid": "p0000526", "repository": "USAP-DC", "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "uid": "600152", "west": -180.0}]

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Dataset Title/Abstract/Map	NSF Award(s)	Date Created	PIs / Scientists	Project Links	Abstract	Bounds Geometry	Geometry	Selected	Visible
d15N and d18O of air in the WAIS Divide ice core	0538657	2023-10-20	Severinghaus, Jeffrey P.	Nitrogen and Oxygen Gas Isotopes in the WAIS Divide Ice Core as Constraints on Chronology, Temperature, and Accumulation Rate	Major gas components of air data set, containing d15N, d18O of O2, dO2/N2, and dAr/N2 from the WAIS Divide ice core at high resolution. These data are used to constrain surface temperature, biosphere oxygen cycling, and firn thickness through the past >60 kyr.	["POINT(-112.05 -79.28)"]	["POINT(-112.05 -79.28)"]	false	false
Taylor Glacier CO2 Isotope Data 74-59 kyr	1245659 1245821 1246148	2022-08-23	Menking, James; Shackleton, Sarah; Bauska, Thomas; Buffen, Aron; Brook, Edward J.; Barker, Stephen; Severinghaus, Jeffrey P.; Dyonisius, Michael; Petrenko, Vasilii; Menking, Andy	Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive	High-precision carbon isotope data (d13C-CO2) show atmospheric CO2 during Marine Isotope Stage 4 (MIS 4, ~70.5-59 ka) was controlled by a succession of millennial-scale processes. Enriched d13C-CO2 during peak glaciation suggests increased ocean carbon storage. Variations in d13C-CO2 in early MIS4 suggest multiple processes were active during CO2 drawdown, potentially including decreased land carbon and decreased Southern Ocean air-sea gas exchange superposed on increased ocean carbon storage. CO2 remained low during MIS 4 while d13C-CO2 fluctuations suggest changes in Southern Ocean and North Atlantic air-sea gas exchange. A 7 ppm increase in CO2 at the onset of Dansgaard-Oeschger event 19 (72.1 ka) and a 22 ppm increase in CO2 during late MIS 4 (Heinrich Stadial 6, ~63.5-60 ka) involved additions of isotopically light carbon to the atmosphere. The terrestrial biosphere and Southern Ocean air-sea gas exchange are possible sources, with the latter event also involving decreased ocean carbon storage.	["POLYGON((161 -77.7,161.1 -77.7,161.2 -77.7,161.3 -77.7,161.4 -77.7,161.5 -77.7,161.6 -77.7,161.7 -77.7,161.8 -77.7,161.9 -77.7,162 -77.7,162 -77.71000000000001,162 -77.72,162 -77.73,162 -77.74,162 -77.75,162 -77.76,162 -77.77,162 -77.78,162 -77.78999999999999,162 -77.8,161.9 -77.8,161.8 -77.8,161.7 -77.8,161.6 -77.8,161.5 -77.8,161.4 -77.8,161.3 -77.8,161.2 -77.8,161.1 -77.8,161 -77.8,161 -77.78999999999999,161 -77.78,161 -77.77,161 -77.76,161 -77.75,161 -77.74,161 -77.73,161 -77.72,161 -77.71000000000001,161 -77.7))"]	["POINT(161.5 -77.75)"]	false	false
Tomographic Imaging of the Velocity and Magnetic Fields in the Sun's Atmosphere	0632399	2016-01-01	Jefferies, Stuart M.	Tomographic Imaging of the Velocity and Magnetic Fields in the Sun's Atmosphere	The ultimate goal of this project is to determine the structure and dynamics of the Sun's atmosphere, assess the role of MHD waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun's atmosphere couples to the solar interior. As the solar atmosphere is 'home' to many of the solar phenomena that can have a direct impact on the biosphere, including flares, coronal mass ejections, and the solar wind, the broader impact of such studies is that they will lead to an improved understanding of the Sun-Earth connection. Under the current award we have developed a suite of instruments that can simultaneously image the line-of-sight Doppler velocity and longitudinal magnetic field at four heights in the solar atmosphere at high temporal cadence. The instruments use magneto-optical filters (see Cacciani, Moretti and Rodgers, Solar Physics 174, p.115, 2004) tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), 770 nm (K) and 1083 nm (He). These lines sample the solar atmosphere from the mid-photosphere to the high-chromosphere. A proof-of-concept run was made in the Austral summer of 2007/2008 using the Na and K versions of the instruments. Here we recorded over 40 hours of full-disk, intensity images of the Sun in the red and blue wings of the Na and K Fraunhofer lines, in both right- and left-circularly polarized light. The images were obtained at a rate of one every five seconds with a nominal spatial resolution of 4 arc-seconds. The run started at 09:44 UT on February 2, 2008 and ended at 03:30 UT on February 4, 2008. Data Quality Assessment: The temperature controls of the instrument housings were unable to fully compensate for the harse Antartic winds encountered during the observing run. This led to large (~15 C) temperature swings which adversely affected the instruments (and thus data quality) in two ways: 1) Crystals of Na and K were deposited on the magneto-optical filter windows leading to "hot spots" in the images. These "hot spots" come and go with time as the temperature changes. 2) The changing temperature caused the optical rails to contract and expand causing the final images to go in- and out-of-focus, thus reducing the resolution to greater than 4 arc-seconds. Both these effect are worse in the K data. Despite these problems, the intensity images can be combined to provide magnetic images that show a very high sensitivity (< 5 Gauss in a 5 second integration). Data Description: The raw data are stored as a series of 1024x1024x4 FITS images. The format is: blue image (left circulary polarized light), blue image (right circularly polarized light), red image (left circulary polarized light), red image (right circularly polarized light). The naming convention for the images is: Type_Instrument_Day_hour_minutes_seconds where Type is I (intensity), F (flatfield), D (dark) Instrument is 0 (Na), 1 (K) Day is the day number from the beginning of the year where January 1 is day 0 For example, I_0_32_12_34_40.fits is an intensity image taken with the Na instrument at 12:34.40 UT on February 2, 2008. Notes: 1) The flatfield images were acquired by moving a diffuser in front of the Sun during the integration. The resulting images therefore have to be corrected for residual low-spatial frequencies due to the non-flat nature of the light source. 2) Each FITS file header contains a variety of information on the observation, e.g., F_CNTO : number of summed frames in each 5 second integration () FPS : Camera frame rate (Frames Per Second) FLIP : Rate at which the half-wave rotator (magnetic switch) was switched INT_PER : Integration time (in seconds) MOF : Temperature of magneto-optical filter cell WS : Temperature of wing selector cell TEMP_0 : Temperature of camera 0 TEMP_1 : Temperature of camera 1 TEMP_2 : Temperature inside instrument (location 1) TEMP_3 : Temperature of narrowband filter TEMP_5 : Temperature of magnets surrounding MOF cell TEMP_6 : Temperature inside instrument (location 2) TEMP_7 : Temperature of housing for magnetic switch () This is the frame count for the camera. The number of frames in each image for the two different polarization states, is half this number. The measured temperatures are only coarse measurements. 3) Due to reflection in the final polarizing beam splitter (which separates the "red" and "blue" signals into the two cameras), the camera 1 data need to "reversed" along the x-axis (i.e. listed as [1024:1] instead of [1:1024]) 4) Line-of-sight velocity and magnetic field images are generated from the observed intensity images. Doppler images as (red-blue)/(red+blue), magnetic images as the difference between the Doppler images for right- and left-circularly polarized light.	["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))"]	["POINT(0 -89.999)"]	false	false

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