Drainage and refill of an Antarctic Peninsula subglacial lake reveals an active subglacial hydrological network

• Main Authors: Hodgson, Dominic A., Jordan, Tom A., Riley, Teal R., Fretwell, Peter T.
• Format: Text
• Language: English
• Published: 2022
• Subjects: Antarctic; The Antarctic; Antarctic Peninsula; Mars Glacier; Antarc*; Ice Sheet
• Online Access: https://doi.org/10.5194/tc-2022-144; https://tc.copernicus.org/preprints/tc-2022-144/

The role of subglacial hydrological networks and subglacial lakes in modulating ice dynamics under the East and West Antarctic Ice Sheets is now relatively well understood. In contrast, little is known about subglacial water bodies under the Antarctic Peninsula Ice Sheet and how these are influencing glacier behaviour. Here we describe the rapid drainage and slow refill of a subglacial lake under Mars Glacier using remote sensing and aerogeophysics platforms. Results suggest drainage of the subglacial lake occurred prior to 2013, resulting in collapse of the overlying ice into the newly formed subglacial cavity. The lake has been refiling since this time, with peak rates of infilling associated with seasonal meltwater activity. We review evidence for similar features elsewhere in the Antarctic Peninsula and discuss whether their appearance marks a threshold shift in the thermal regime of the region’s glaciers and the activation of their subglacial hydrological networks. Collectively, these features show coupling of surface climate processes and the bed and may help explain the strong seasonality seen in glacier flow rates during the annual melt season and the ongoing regional decline in ice mass.