USAP-DC

Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. Since its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public's fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth's last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.

Person	Role
Corso, Andrew	Investigator and contact
Desvignes, Thomas	Co-Investigator
McDowell, Jan	Co-Investigator
Cheng, Chi-Hing	Co-Investigator
Biesack, Ellen	Co-Investigator
Steinberg, Deborah	Co-Investigator
Hilton, Eric	Co-Investigator

Unknown Program	Award # None
Antarctic Integrated System Science	Award # 2224611
Antarctic Integrated System Science	Award # 2026045
Antarctic Organisms and Ecosystems	Award # 1543383
Antarctic Integrated System Science	Award # 1440435
Antarctic Organisms and Ecosystems	Award # 1440435
Antarctic Organisms and Ecosystems	Award # 1344502
Antarctic Organisms and Ecosystems	Award # 1142158
Antarctic Organisms and Ecosystems	Award # 0636696

USAP-None_1

x_iceGBS_dataManagementPlan_REVISED.docx

1. Akarotaxis gouldae, a new species of Antarctic dragonfish (Notothenioidei: Bathydraconidae) from the western Antarctic Peninsula (doi:10.11646/zootaxa.5501.2.3)
2. Larval stages of the Antarctic dragonfish Akarotaxis nudiceps (Waite, 1916), with comments on the larvae of the morphologically similar species Prionodraco evansii Regan 1914 (Notothenioidei: Bathydraconidae) (doi:10.1111/jfb.15267)
3. Sedwick, P. N., Sohst, B. M., O’Hara, C., Stammerjohn, S. E., Loose, B., Dinniman, M. S., Buck, N. J., Resing, J. A., & Ackley, S. F. (2022). Seasonal Dynamics of Dissolved Iron on the Antarctic Continental Shelf: Late‐Fall Observations From the Terra Nova Bay and Ross Ice Shelf Polynyas. Journal of Geophysical Research: Oceans, 127(10). Portico. (doi:10.1029/2022jc018999)
4. Davison, B. J., Hogg, A. E., Moffat, C., Meredith, M. P., & Wallis, B. J. (2024). Widespread increase in discharge from west Antarctic Peninsula glaciers since 2018. The Cryosphere, 18(7), 3237–3251. (doi:10.5194/tc-18-3237-2024)
5. Eveleth, R., Cassar, N., Sherrell, R. M., Ducklow, H., Meredith, M. P., Venables, H. J., … Li, Z. (2017). Ice melt influence on summertime net community production along the Western Antarctic Peninsula. Deep Sea Research Part II: Topical Studies in Oceanography, 139, 89–102. (doi:10.1016/j.dsr2.2016.07.016)
6. Marcondes, M. C. C., Cheeseman, T., Jackson, J. A., Friedlaender, A. S., Pallin, L., Olio, M., … Sousa-Lima, R. S. (2021). The Southern Ocean Exchange: porous boundaries between humpback whale breeding populations in southern polar waters. Scientific Reports, 11(1). (doi:10.1038/s41598-021-02612-5)
7. Gray, P. C., Bierlich, K. C., Mantell, S. A., Friedlaender, A. S., Goldbogen, J. A., & Johnston, D. W. (2019). Drones and convolutional neural networks facilitate automated and accurate cetacean species identification and photogrammetry. Methods in Ecology and Evolution, 10(9), 1490–1500. (doi:10.1111/2041-210x.13246)
8. Brown, M. S., Bowman, J. S., Lin, Y., Feehan, C. J., Moreno, C. M., Cassar, N., … Schofield, O. M. (2021). Low diversity of a key phytoplankton group along the West Antarctic Peninsula. Limnology and Oceanography. (doi:10.1002/lno.11765)
9. Larsen, G. D., Cimino, M. A., Dale, J., Friedlaender, A. S., Goerke, M. A., & Johnston, D. W. (2025). Terrestrial Spatial Distribution and Summer Abundance of Antarctic Fur Seals (Arctocephalus gazella) Near Palmer Station, Antarctica, From Drone Surveys. Ecology and Evolution, 15(4). e70833. (doi:10.1002/ece3.70833)
10. Lohmann, A. C., Morton, J. P., Schofield, O. M., & Nowacek, D. P. (2023). Cyclical prey shortages for a marine polar predator driven by the interaction of climate change and natural climate variability. Limnology and Oceanography. Portico. (doi:10.1002/lno.12453)