Subglacial Lakes: Location & Activity

Subglacial Lakes: Location & Activity

One of the most striking features of subglacial hydrology are subglacial lakes. Some 379 subglacial lakes have been identified beneath ice sheet (Wright and Siegert, 2012), some of which have been observed to be dynamically active with episodic lake filling and draining events. The lakes have the capacity to store, and periodically release, a portion of the estimated 65 Gt of water generated annually through subglacial melting. New active subglacial lakes can be detected by measuring the episodic surface elevation change of the ice sheet with altimetry satellite missions, and this technique was used to identify new active subglacial lakes in the ESA 4DAntarctica project.

Lake activity under the Thwaites Glacier, surface elevation change after 4 lakes drained in 2013.

Summary of active subglacial lake datasets planned within 5DAIS:

• Continue the analysis carried out as part of 4DAntarctica (Malczyk et al., 2020; Malczyk et al., 2023; Wearing et al., 2024) by using swath mode CS2 altimetry data to measure surface elevation change over subglacial lakes.
• Extend the time series of activity for all known active lakes.
• Derive timing and fluxes of lake drainage and refill, documenting new events.