Thwaites glacier seen by Copernicus Sentinel-2

At around 120 km wide, Thwaites is the largest glacier on Earth and one of the most fragile glaciers in Antarctica. Imaged here by Copernicus Sentinel-2 on 26 November 2020, it’s hard to imagine what’s going on deep below the ice. Hidden from view by ice kilometres thick, there is a vast network of lakes and streams at the base of the Antarctic ice sheet. Using more than 10 years’ worth of altimetry data from ESA’s CryoSat satellite, scientists discovered that the lakes beneath Thwaites, the largest of which is over 40 km long, drained in quick succession, in 2013 and then in 2017. This kind of drainage under Thwaites has never before been recorded. Scientists estimate that the rate of drainage peaked at about 500 cubic metres a second – possibly the largest outflow of meltwater ever reported from subglacial lakes in this region.

Read full story: CryoSat reveals surprising ebb and flow of subglacial lakes