Canada (Commonwealth Union) – The Antarctic ice sheet is one of the two polar ice caps in the world. It covers almost the entire Antarctic continent and is the biggest single mass of ice in the world.
A 460km river below the Antarctica ice sheet has been discovered. A study team led by the University of Waterloo’s Dr. Christine Dow, a professor in the department of Geography and Environmental Management and cross-appointed to the Department of Applied Mathematics, found the river from a series of airborne radar observations and models. The results indicate the ice sheet’s base has increased active water flow than perceived on prior occasions, which may make it more vulnerable to changes in climate.
“From satellite measurements, we know which regions of Antarctica are losing ice and how much, but we don’t necessarily know why,” said Dr Dow, a Waterloo Climate Institute member. “This discovery could be a missing link in our models. We could be hugely underestimating how quickly the system will melt by not accounting for the influence of these river systems.”
The Antarctic Weddell Sea region, where the research is taking place, has sufficient ice to increase the sea level worldwide by 4.3 meters, and the newly found river will have a significant part in that sea level rise. Dow and her colleagues indicated that the large volume of freshwater pumped from the river into the ocean results in more melting at the sensitive region where ice moves into the ocean starting to float. In the future, if warm air temperatures results in sufficient surface melt to reach the ice sheet’s base, it may tip Antarctica to a Greenland-like state, resulting in elevated volumes of freshwater moving into the ocean. More freshwater in the river may result in elevated ice shelf melt, dwarfing the ice sheet, and more ice flow rates, according to the researchers.
