Antarctica's Seasonal Meltwater Networks More Extensive Than Previously Thought
A new continent-wide survey revealed that the meltwater systems flowing over parts of Antarctica's ice during its brief summer are more extensive than previously thought.
The survey, described in a paper published in the journal Nature, showed that there are nearly 700 seasonal meltwater systems of interconnected channels, ponds and braided streams all over the continent.
"This is not in the future -- this is widespread now and has been for decades," said Jonathan Kingslake, a glaciologist at Columbia University's Lamont-Doherty Earth Observatory and lead author of the study, in a press release. "I think most polar scientists have considered water moving across the surface of Antarctica to be extremely rare. But we found a lot of it, over very large areas."
For the study, the researchers systematically cataloged images of surface water taken from military aircraft since 1947 and satellite imagery conducted from 1973 onwards. The researchers observed that meltwater ponds lurking in Antarctica can be up to several miles wide. On the other hand, channels and streams can run as far as 75 miles, starting from as close as 375 miles from the South Pole at 4,300 feet above sea level.
"This study tells us there's already a lot more melting going on than we thought," shared Robin Bell, a polar scientist at Lamont-Doherty Earth Observatory and co-author of the study, in a statement. "When you turn up the temperature, it's only going to increase."
The survey also showed that many of the meltwater streams and channels begin near mountains, poking through glaciers or in areas with little or no snow, exposing the underlying bluish ice.
Because the ice exposed in these areas are darker than those in snow-covered areas, it absorbs more solar energy and is more prone to melting. As the ice melts, liquid water will create a path downhill through overlying snow.
The researchers noted that the increasing temperature in the Antarctic area could greatly affect the meltwater systems. If the temperature in the continent continues to rise as predicted this century, the researchers worry that the melting process will occur on a much larger scale.