Melting of ice shelves in West Antarctica speeds up and slows down in response to changes in deep ocean temperature, and is far more variable than previously thought, according to new research published this week in the journal Nature Geoscience.
Scientists studying seawater temperatures in the Amundsen Sea – part of the West Antarctic Ice Sheet (WAIS) – found a cycle of warming and cooling in the ocean over the 16 years of their observations. They show for the first time that while mass loss from the ice sheet increased during a warm period, it steadied and in some cases decreased during cooler phases. The authors also show evidence for linking this cycle to El Nino in the tropical Pacific Ocean.
These findings are important for enabling better predictions about how much glacial melt will contribute to global sea-level rise.
During eight Antarctic summers from 2000-2016 an international team of scientists from the UK, US and South Korea, observed changes in ocean temperature, salinity and currents near the Dotson Ice Shelf – an area of floating ice over three times the size of Greater London and seven times the size of New York City.
Read more at British Antarctic Survey
Image: Ocean samples were collected from three polar vessels including the RRS James Clark Ross. (Credit: British Antarctic Survey)