Expansion of glacial lakes on Nelson and King George Islands, Maritime Antarctica, from 1986 to 2020

Abstract

This study aims to quantify the areal variation of glacial lakes in the coastal ice-free areas of King George Island (KGI) and Nelson Island (NI) from 1986 to 2020. Glacial lake and glacial area fluctuations are estimated using spaceborne remote sensing data and annual mean near-surface air temperature data from station observations and ERA-Interim reanalysis were analyzed. The area of glacial lakes expanded 732%, from 0.18 km2 in the 1980s to 1.39 km2 in 2020. For the 1988–2000/2003 and 2000/2003–2020 periods, the increase in NI lake area is estimated to be 190% and 86%, respectively. Meanwhile, on KGI, the increase is estimated to be 316% for the 1988–2000/2003 period and 103% for the 2000/2003–2020 period. The majority of lakes and higher lake expansions occurred at the glacier fronts and can be attributed to the melting of glacier fronts and the subsequent glacial retreat in recent decades.