The Totten Glacier is East Antarctica’s largest and most rapidly thinning glacier. Deep, warm water has been observed seaward of the glacier before, but up to now there was no evidence that it could compromise coastal ice.
The result is significant because the ice flowing through Totten Glacier alone is sufficient to raise global sea level by at least 11 feet, equivalent to the contribution of the West Antarctic Ice Sheet if it were to completely collapse.
‘The ocean is melting ice in an area of the glacier that we thought was totally cut off before,’ says Greenbaum, adding that ‘knowing this now will improve predictions of ice melt and the timing of future glacier retreat.’
Given that previous work has shown that the basin has drained its ice to the ocean and filled again many times in the past, this study uncovers a means for how that process may be starting again.
‘We’ve basically shown that the submarine basins of East Antarctica have similar configurations and coastal vulnerabilities to the submarine basins of West Antarctica that we’re so worried about, and that warm ocean water, which is having a huge impact in West Antarctica, is affecting East Antarctica, as well,’ says researcher Donald Blankenship.
The deeper of the two gateways identified in the study is a three-mile-wide seafloor valley extending from the ocean to beneath Totten Glacier in an area not previously known to be floating. Identifying the valley was unexpected because satellite analyses conducted by other teams had indicated the ice above it was resting on solid ground.