Towards an improved heat budget for the floating glaciers in Antarctica
Anna Wahlin, University of Gothenburg, Sweden
The most rapid melting of Antarctic shelf regions is occurring in the Amundsen Sea, mainly the result of a seaward surge of the West Antarctic Ice Sheet, a decline driven by warm salty ocean currents that accesses the floating glaciers through bathymetric troughs, melting the glacial ice from below.
Due to limited in-situ data, in particular from the central part of the Antarctic shelf, the main pathways of the warm deep water are poorly known and budgets for ocean heat, salt and freshwater on the shelf and at the terminus of the ice sheet have not been quantified.
The University of Gothenburg has recently been funded to carry through a major part of a multinational project together with Korea, US, Great Britain and Norway to collect data during 2014-2018, from autonomous moorings and hydrographic transects on two cruises with the Korean RVIB Araon to the region.
The cruises plan to quantify budgets for oceanic heat, salt and glacier melt water for the central Amundsen Shelf. The project also plans to quantify the variability of the oceanic heat transport on the shelf on time scales up to centennial, and will determine the importance of winds and large-scale ocean circulation as forcing factors for the inflow of warm water onto the shelf.
From these measurements, the oceanic heat loss and glacier melt water production on the central Amundsen Shelf will be calculated and joined with existing estimates from other parts of the West Antarctic Ice Sheet.
As well, the time series of the oceanic heat transport will be analysed and correlated to wind and large-scale ocean circulation in order to determine their relative importance in forcing the warm water onto the shelf.
Mooring data from the deep trough in the central Amundsen Sea shelf area and hydrographic transects across the deep trough will be published in the National Oceanographic Data Centre (NODC, USA), submitted to the NODC within two years of retrieval.
Other key participants
HK. Ha (KOPRI, Korea)
SH. Lee (KOPRI, Korea)
K. Assmann (University of Gothenburg, Sweden)
O. Kalén (University of Gothenburg, Sweden)
L. Arneborg (University of Gothenburg, Sweden)
G. Björk (University of Gothenburg, Sweden)