Email Communication: Dr. Laurence Padman via Dr. Helen Fricker

June 30, 2017

Water under and near Larsen C is very cold [1], [2], formed mostly by sea ice freezing on the continental shelf {could find a couple of cites if needed}. The oceanographic setting of Larsen C makes it difficult to get warm water under the ice shelf, so that the rapid melting measured under Amundsen Sea ice shelves is unlikely to occur under Larsen C.  Even in a simulation with projected future climate where warm water flows into the Filchner Ice Shelf in the southern Weddell Sea [3],[4], the water near Larsen C stays cold.  That is, we don’t expect Larsen C basal melting to increase much if at all.  However, if the atmospheric warming experienced over the last several decades was to continue, the ice shelf could be destroyed by surface meltwater.

[1] Nicholls, K.W., Makinson, K. and Venables, E.J., 2012. Ocean circulation beneath Larsen C Ice Shelf, Antarctica from in situ observations. Geophysical Research Letters, 39(19).

[2] Nicholls, K. W., C. J. Pudsey, and P. Morris (2004), Summertime water masses off the northern Larsen C Ice Shelf, Antarctica, Geophys. Res. Lett., 31, L09309,

doi:10.1029/2004GL019924.

[3] Hellmer, H.H., Kauker, F., Timmermann, R., Determann, J. and Rae, J., 2012. Twenty-first-century warming of a large Antarctic ice-shelf cavity by a redirected coastal current. Nature, 485(7397), pp.225-228.

[4] Hellmer, H.H., Kauker, F., Timmermann, R. and Hattermann, T., 2017. The fate of the southern Weddell Sea continental shelf in a warming climate. Journal of Climate, 30(12), pp.4337-4350.