| Summary: | As many ice shelves on the Antarctic Peninsula are meeting a similar unfortunate fate, the role of surface water in the disintegration of these ice shelves has received considerable attention. This study uses 24 Sentinel-1 images to investigate trends in backscatter signature for surface lakes on George VI for the austral summer and winter of 2017/18. This study aims to understand how the backscatter signal evolves through time, and whether external controls such as climatic events influence this. The study investigates the development of surface lakes throughout the summer, measuring 1,300 surface lakes at the height of the melt season, and identifying ribbon lakes as the predominant lake type. A potential relationship between backscatter signature of surface lakes and snowfall events is identified, as a heavy snowfall event in November corresponds with an engulfment of low backscatter signature as wet snow saturates the return signal. A specific backscatter signature on George VI of surface lakes is cyclical, with a pattern of −6 dB (beginning of melt season), −12 dB (lakes developing), −15 dB at peak melt, −8 dB for lake burial, and signatures between −4 dB and −7 dB for lake freeze-over in June. By analysing the Sentinel-1 imagery into June, it was possible to identify a date of freeze-through of the surface lakes at the end of May 2018. This study aims to shed light on the C-band backscatter signature to aid automated identification of surface lakes to protect the health of the Antarctic ice shelves.
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