While everyone has been alarmed by the consequences of climate change on polar ice caps and glaciers, scientists have confirmed the existence of yet another factor contributing to the melting of ice sheets in Greenland. This time, it is completely a natural phenomenon, not induced by human activities.
When a glacier, which has a bedrock below sea level, moves in such a way that in abrades its bedrock underneath, fjords are formed. Fjords are narrow parts of seas found between cliffs. A group of scientists from the Arctic Research Centre (ARC) in Aarhus University, Denmark, and the Greenland Institute of Natural Resources studied a fjord known as Young Sound, for a span of more than a decade. The group discovered that the Earth’s internal heat coming from the deep under the fjord is actually warming up the bottom water of the fjord and eventually making glaciers on the ice sheet to move down to the sea.
“Northeast Greenland has several hot springs where the water becomes up to 60 degrees [Celsius] warm and, like Iceland, the area has abundant underground geothermal activity,” explained Soren Rysgaard of ARC. The earth’s core has a temperature of about 6,000 degrees Celsius, which is comparable to the sun’s surface. This internal heat manifests on the surface as volcanic eruptions and hot springs. “There is no doubt that the heat from the Earth’s interior affects the movement of the ice, and we expect that a similar heat seepage takes place below a major part of the ice cap in the northeastern corner of Greenland,” continued Rysgaard, who led the research team.
According to the data gathered, the scientists have quantified the
earth’s internal heat absorbed by the fjord. The heat absorbed was about 100 megawatt per square meter, which “corresponds to a 2-megawatt wind turbine sending electricity to a large heater at the bottom of the fjord all year round.”
Nonetheless, Rysgaard emphasized that it is only one of the factors causing the melting of ice sheets in Greenland. “It is a combination of higher temperatures in the air and the sea, precipitation from above, local dynamics of the ice sheet and heat loss from the Earth’s interior that determines the mass loss from the Greenland ice sheet,” Rysgaard explained.