2022-2023 USAP Field Season
CAREER: The transformation, cross-shore export, and along-shore transport of freshwater on Antarctic shelves
Mr. Carlos F Moffat
Supporting Stations: ARSV Laurence M. Gould
Freshwater discharges from high-latitude continental ice glacial reserves strongly modulate salt budgets, circulation, and associated ocean water mass formation on polar ice shelves. The research component of this project aims to improve understanding of the dynamics of freshwater discharge around the Antarctic continent. Associated research questions pertain to (1) the controls on the cross- and along-shelf spreading of fresh, buoyant coastal currents,(2) the role of distributed coastal freshwater sources (as opposed to 'point' source river outflow sources typical of lower latitudes), and (3) the contribution of these coastal currents to water mass transformation and heat transfer on the continental shelf. The PI seeks an observational deployment to measure a specific, previously-identified example of a coastal freshwater-driven current, the Antarctic Peninsula Coastal Current (APCC).
Field Season Overview
Two individuals will participate on cruises aboard the ARSV Laurence M. Gould (LMG) between late December and February where they will characterize glacial discharge with sustained, high-resolution surveys using both autonomous gliders and vessel-based CTD surveys. As part of a collaboration with the Palmer Long Term Ecology Research (PAL-LTER) program and British Antarctic Survey (BAS), the science team will target the freshwater front found off the coast between Palmer Station and Marguerite Bay, which is also adjacent to the PAL-LTER sampling grid. Four dedicated ship days during the cruise will allow the team to deploy two Teledyne Slocum Gliders and conduct vessel-based hydrographic and velocity surveys that will cover a fraction of the shelf that includes a 40-50 km band from the shore of the islands between Anvers and Adelaide. Vessel-based hydrographic surveys and water collection off the Antarctic shelf using the CTD and rosette will augment the glider surveys and PAL-LTER sampling grid. CTD surveys for this project will occur at three separate cross-shore sections within the PAL-LTER grid.
Deploying Team Members