The surface of Lake Askja is frozen again
The entire surface of Lake Askja is now frozen again after all the ice was broken up and melted earlier this winter. There is evidence that increased geothermal heat in the area triggered this process, but the winds and mixing have helped. This is confirmed by Ingibjörg Jónsdóttir, geographer and dean of the Department of Earth Sciences at the University of Iceland.
Jónsdóttir says it is normal for the lake to freeze again now, as the area has been subject to a lot of frost in the last few days and because of the nature of fresh water. She points out that the surface of the lake has been frozen for the most part since Friday.
Exciting to watch what happens next
“In unsalted water, the density is mostly about four degrees, and if it gets colder than that, the part of the water gets lighter and stays on the surface and becomes strongly layered, and you just really have to cool the top part and that’s when the ice forms very fast.”
She says it is no surprise that the surface of the lake is now frozen, but says it is exciting to watch what happens next.
“There is evidence that the geothermal heating has increased recently. We will see in the coming days whether it was a passing phase or whether it will continue. We will see whether this ice is allowed to remain in peace or not.”
She states that if the ice melts, scientists will get a better indication of what is happening at Lake Askja.