Even though the sun does not shine in Antarctica in winter, in some places snow on the glaciers can melt. The cause: warm wind. Utrecht glacier researcher Peter Kuipers Munneke discovered that fact by combining the results of weather stations and satellite images. His findings were published in Geophysical Research Letters on Wednesday 2 May.
Winter in Antarctica is pitch black and freezing cold for months on end. In the interior of the continent, temperatures can drop to -80 Celsius. On the coast, however, the winter is usually a bit milder: around -25 degrees Celsius. It now turns out that at those relatively warm spots around the coast, winter temperatures can be even warmer. When the mercury rises above zero, snow begins to melt, causing several meltwater lakes to accumulate on top of the underlying glacier. These lakes can be fifty meters wide, up to a kilometer in length and one or to two meters deep.
No solar heat
Glacier researcher Peter Kuipers Munneke from Utrecht University’s (UU) climate institute IMAU was the leader of the study in which UU cooperated with several institutes from the UK and the US. Kuipers Munneke was surprised by the findings. “The meltwater lakes occur on the Larsen C ice sheet, a large floating glacier in the north of Antarctica, where a large iceberg broke off just last July. We hadn’t expected it to melt so much there in the winter, because it’s so dark there, and the sun provides absolutely no heat. Four years ago, we installed a weather station there to study why so much snow melts in the area. Unexpectedly, it’s due to the melting in the winter, which appears to be caused by the warm wind.”