Recent Deceleration of the Ice Elevation Change of Ecology Glacier (King George Island, Antarctica)

Glacier change studies in the Antarctic Peninsula region, despite their importance for global sea level rise, are commonly restricted to the investigation of frontal position changes. Here we present a long term (37 years; 1979-2016) study of ice elevation changes of the Ecology Glacier, King George Island (62 degrees 11'S, 58 degrees 29'W). The glacier covers an area of 5.21 km(2) and is located close to the H. Arctowski Polish Antarctic Station, and therefore has been an object of various multidisciplinary studies with subject ranging from glaciology, meteorology to glacial microbiology. Hence, it is of great interest to assess its current state and put it in a broader context of recent glacial change. In order to achieve that goal, we conducted an analysis of archival cartographic material and combined it with field measurements of proglacial lagoon hydrography and state-of-art geodetic surveying of the glacier surface with terrestrial laser scanning and satellite imagery. Overall mass loss was largest in the beginning of 2000s, and the rate of elevation change substantially decreased between 2012-2016, with little ice front retreat and no significant surface lowering. Ice elevation change rate for the common ablation area over all analyzed periods (1979-2001-2012-2016) has decreased from -1.7 +/- 0.4 m/year in 1979-2001 and -1.5 +/- 0.5 m/year in 2001-2012 to -0.5 +/- 0.6 m/year in 2012-2016. This reduction of ice mass loss is likely related to decreasing summer temperatures in this region of the Antarctic Peninsula.