North America Heat Waves Led to Unprecedented Ice Melt in Greenland

Source: By Laura Millan Lombrana, Bloomberg • Posted: Thursday, October 6, 2022

Average temperatures in most of Greenland were more than 8C above the 30-year average for September, according to Copernicus

Melt ponds in Greenland's Sugar Loaf Bay captured by Copernicus Sentinel-2 on Aug. 29

Melt ponds in Greenland’s Sugar Loaf Bay captured by Copernicus Sentinel-2 on Aug. 29 ESA

Strong winds carried extreme heat from the western US, Canada and the Atlantic ocean over Greenland in September, bringing average temperatures more than 8 degrees Celsius above the 30-year average and causing record ice melt.

Almost all of Greenland experienced the highest average temperatures in any month of September since records started in 1979, according to a monthly report by Europe’s Earth observation agency Copernicus. A different set of data by the US National Snow and Ice Data Center detected temperatures above 0C at Summit Station — over 3,200 meters (10,500 feet) above sea level — for the first time in September since measurements began in 1989.

The heat wave resulted in an unprecedented melt event for this time of the year that peaked between Sept. 2 and 5, according to the NSIDC. On Sept. 3, surface melting was happening on more than a third of the ice sheet, which stretches across about 600,000 square kilometers (232,000 square miles), an area equivalent to California and Nebraska combined.

Ice loss from the Greenland ice sheet is one of the largest contributors to rising sea levels globally. The melting has accelerated in recent decades and would continue even if the burning of fossil fuels that generates planet-warming gas emissions halted overnight, according to a paper published in August in Nature Climate Change. Using a combination of satellite observations and climate models, scientists concluded that Greenland ice melting will lead to a minimum sea rise of 27 centimeters (10.6 inches), regardless of future climate warming scenarios.

Globally, this was the joint fourth-warmest September for the past three decades, together with 2016, according to Copernicus. Temperatures were about 0.3C above the 1991-2020 period.