Surface mass balance of small glaciers on James Ross Island, north-eastern Antarctic Peninsula, during 2009-2015

摘要

Two small glaciers on James Ross Island, the north-eastern Antarctic Peninsula, experienced surface mass gain between 2009 and 2015 as revealed by field measurements. A positive cumulative surface mass balance of 0.57 +/- 0.67 and 0.11 +/- 0.37 m w.e. was observed during the 2009-2015 period on Whisky Glacier and Davies Dome, respectively. The results indicate a change from surface mass loss that prevailed in the region during the first decade of the 21st century to predominantly positive surface mass balance after 2009/10. The spatial pattern of annual surface mass-balance distribution implies snow redistribution by wind on both glaciers. The mean equilibrium line altitudes for Whisky Glacier (311 +/- 16 m a.s.l.) and Davies Dome (393 +/- 18m a.s.l.) are in accordance with the regional data indicating 200-300 m higher equilibrium line on James Ross and Vega Islands compared with the South Shetland Islands. The mean accumulation-area ratio of 0.68 +/- 0.09 and 0.44 +/- 0.09 determined for Whisky Glacier and Davies Dome, respectively, is similar to the value reported for Vega Island and within the range of typical values for high-latitude glaciers.