ScienceDaily [sciencedaily.com]:
Newly discovered deep seabed channels beneath Thwaites Glacier in West Antarctica may be the pathway for warm ocean water to melt the underside of the ice. Data from two research missions, using aircraft and ship, are helping scientists to understand the contribution this huge and remote glacier is likely to make to future global sea level rise.
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Over the past 30 years, the overall rate of ice loss from Thwaites and its neighbouring glaciers has increased more than 5-fold. Already, ice draining from Thwaites into the Amundsen Sea accounts for about four percent of global sea-level rise. A run-away collapse of the glacier could lead to a significant increase in sea levels of around 65 cm (25 inches) and scientists want to find out how quickly this could happen.Lead author Dr Tom Jordan, an aero-geophysicist at British Antarctic Survey (BAS), who led the airborne survey, says:
"It was fantastic to be able to map the channels and cavity system hidden beneath the ice shelf; they are deeper than expected -- some are more than 800 metres deep. They form the critical link between the ocean and the glacier.
The researchers hope the additional data will improve models projecting ice loss in Antarctica.