USAP-DC

The ice shelves around the perimeter Antarctica hold back inland ice that has the potential to raise global sea level by meters. By how much and how rapidly this could occur is a central question in glaciology. The underside of these ice shelves is in contact with the ocean, and there are signs that warming of ocean water is causing melting and retreat of these shelves, with direct implications for sea-level rise. This project will seize an emergent opportunity to work with Australian and South Korean colleagues to acquire snapshot profiles of ocean temperature, salinity, and velocity, and improve bathymetric knowledge, where no prior data exist. The team will work near three glaciers draining ice with substantial sea-level potential from the East and West Antarctic Ice Sheets. The targets are Shackleton and Cook Ice Shelves in East Antarctica, and Thwaites Glacier in West Antarctica. An undergraduate student will be engaged through the Scripps Undergraduate Research Fellowship program and the team will work through the Scripps Educational Alliances program to identify educational outreach opportunities through which to build community engagement in this project. The team will use high-resolution general circulation model simulations to optimize sensor targeting (to be deployed from helicopter and fixed-wing aircraft) and evaluate the relative roles of subglacial freshwater discharge and ocean forcing on subglacial melt rates. The aim is to better understand why grounding-line melt rates are higher at the East Antarctic sites despite data indicating warmer ambient ocean temperatures at the West Antarctic sites. Such behavior could be explained by discharge of subglacial freshwater into ice-shelf cavities, but insufficient data currently exist to test this hypothesis. The team aims to build on ongoing international, collaborative airborne oceanographic sampling with colleagues in the Republic of Korea, Australia, and the United States. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Person	Role
Greenbaum, Jamin	Investigator and contact
Auerbach, Daniel	Data Manager

Antarctic Glaciology

Award # 2114454

USAP-2114454_1

Deployment	Type
Jamin S Greenbaum	airborne survey

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	AXCTD and AXBT Profiles from the Amundsen Sea	ZIP Archive	exists

1. J. Greenbaum, T. Pelle, C. Dow, C. Eayrs, C.-K. Lee, W. S. Lee, M. Mazloff, J. Na, H. Seroussi, A. Wåhlin, S.-T. Yoon, S. Yun, Freshwater feedbacks accelerate sea level rise from Thwaites Glacier, West Antarctica. Nature (submitted).