February 19, 2020
Boydell Glacier terminates at the island adjacent to Point A. The accumulation zone between Point A, B and C is on January 12, 2020 has limited gray area indicating bare firn. By Feb. 13 there is considerable cobalt blue snow/firn areas saturated with melt water. The yellow dots mark the margin of the ice sheet and pink dots the margin of the ablation zone on Feb. 13, 2020.
The Boydell Glacier, Antarctic Peninsula is fed in part by a plateau to its north. Boydell Glacier has experienced a substantial retreat of 6.5 km from 2001-2017 and in 1990 was part of the Prince Gustav Ice shelf that has disintegrated (Cook and Vaughan, 2010). Antarctic temperature records were set at Esperenza and Marambio Base. in early February 2020. Here we examine the impact of period of record warm weather over the Antarctic Peninsula on a portion of the Boydell Glacier’s accumulation zone north of its terminus (64.1 S 58.9 W), ~100 km from Esperanza, using Landsat images from January 12-February 13, 2020 to identify surface melt extent and surface melt feature development. A.
Xavier Fettweis, University of Liege Belgium, using the MAR climate model output forced by the Global Forecast System (GFS) to generate daily melt maps for Antarctica, for Esperanza the melt map for recent weeks, shown below indicates that daily melt increased to above 30 mm/day, with a maximum temperature on the warmest day of 18.3 C (65 F). On the Boydell Glacier accumulation plateau is dominated by surface snowpack on January 12, 2020. On Feb. 13, 2020 significant cobalt blue snow/firn melt water saturated zones have developed in the accumulation zone covering 4 km2 and in a few localities in the ablation zone. This melt water will likely refreeze in the firn/snowpack of the accumulation zone and not be lost from the system, whereas melt in the ablation zone near Point A and Point D would be quickly lost from the system. The ablation zone is denoted by pink dots for Feb. 13, 2020..
The Boydell Glacier accumulation zone in 207 and 2018 lacks any melt water saturation features.
The accumulation zone in REMA Antarctica image indicating surface contours at 100 m intervals.
Meltwater production time series at Esperanza Base from MAR-GFS From Xavier Fettweis.