Greenland hit by Europe’s heat wave
Poses critical risk to sea levels around world
The same heat dome that roasted Europe and broke national temperature records in five countries last week has shifted to Greenland, where it is causing one of the biggest melt events ever observed on the fragile ice sheet.
By some measures, the ice melt is more extreme than during a benchmark record event in July 2012, according to scientists analyzing the latest data.
During that event, about 98 per cent of the ice sheet experienced some surface melting, speeding up the process of shedding ice into the ocean.
The fate of Greenland’s ice sheet is of critical importance, since Greenland is the biggest contributor to modern-day sea level rise.
Due to both surface melting and a lack of snow on the ice sheet this summer, “this is the year Greenland is contributing most to sea level rise,” said Marco Tedesco, a climate scientist at Columbia University.
To illustrate the magnitude of ice contained in Greenland, consider that if the entire ice sheet were to melt, it would raise sea levels by seven metres. Scientists are using aircraft, field research, satellites and other tools to improve their understanding of how quickly ice is being lost.
Xavier Fettweis, a climate scientist at University of Liège, tweeted that a computer simulation suggests the rate of melting will reach a maximum on Thursday, which “could be the highest in Greenland history from 1950.”
Already this year, the ice sheet has endured exceptional melting. Between June 11 and 20, the ice sheet lost the equivalent of 80 billion tons of ice, the National Snow and Ice Data Center computed. Melting covered about 270,000 square miles, the most on record so early in the season.
Tedesco said the melting on the ice sheet this summer still trails 2012.
However, the ice sheet’s surface mass balance, which takes into account not only melting but also snow accumulation, is “neck and neck” with 2012, Tedesco said.
Given the ongoing melt event, “there is very good chance we will have a record-breaking (low) surface mass balance,” Tedesco said. The depleted surface mass on the ice sheet is directly tied to its contribution to sea level rise.
The Arctic overall is warming at more than twice the rate of the rest of the globe, which is a trend that has been firmly tied to human emissions of greenhouse gases.