The discussions and debates about global warming and the rise in the global mean sea level has received a rude jolt with the first ever recorded rainfall in Greenland’s ice sheet summit causing ‘widespread’ melting. It was the heaviest rainfall on the ice sheet since record keeping began in 1950. Nearly 7bn tonnes of rain lashed the area from August 14 to 16, say researchers. On August 14, rain was observed at the highest point for several hours, and air temperatures remained above freezing for about nine hours. This was the third time in less than a decade, and the latest date in the year on record, that the US National Science Foundation’s Summit Station had above-freezing temperatures and wet snow. There is no previous report of rainfall at this location which reaches 3,216m (10,551ft) in elevation. 
The Greenland ice sheet is one of two continent-scale ice masses on Earth, with the other being the Antarctic Ice Sheet. The largest ice mass in the Northern Hemisphere, it lies between the Atlantic and the Arctic Ocean. Almost 80% of Greenland’s landmass is covered by the ice sheet, expanding an area over 1.7mn sqkm. Unlike Antarctica, which has almost 75% of its coastline dominated by floating ice shelves, Greenland has only ice tongues. They are fewer in number and are constrained to fjords. 
The loss of ice from the Greenland ice sheet is directly influencing the global mean sea level, in fact greater than the contribution from the Antarctic ice sheets combined. The melt extent peaked at 872,000sqkm on August 14, dropping to 754,000sqkm on the 15th and 512,000sqkm on 16th. Only 2012 and 2021 have had more than one melt event of 800,000sq km in extent, and the August 14 event was the latest date for this scale of melt extent in the satellite record. The total aerial extent of surface melting (total melt-day extent) for 2021 through August 16 is 21.3mn sqkm, tied for the fourteenth highest total to date, and well above the 1981 to 2010 average of 18.6mn sqkm.
Ted Scambos, a senior research scientist at the National Snow and Ice Data Center at the University of Colorado, said this is evidence Greenland is warming rapidly. As human-caused climate change warms the planet, ice loss has rapidly increased. A major UN climate report released this month concluded that the burning of fossil fuels led to Greenland melting over the past two decades. 
A recent study published in the journal Cryosphere found Earth has lost a staggering 28tn tonnes of ice since the mid-1990s, a large portion of which was from the Arctic, including the Greenland ice sheet. Incidentally, the latest rain and melt episode comes on the heels of what happened in July, when the Greenland ice sheet experienced one of the most significant melting events in the past decade, losing more than 8.5bn tonnes of surface mass in a single day, which was enough to submerge Florida in two inches of water. It was the third instance of extreme melting in the past decade, during which time the melting has stretched farther inland than the entire satellite era, which began in the 1970s. In 2019, Greenland shed roughly 532bn tonnes of ice into the sea. During that year, an unexpectedly hot spring and a July heat wave caused almost the entire ice sheet’s surface to begin melting. Global sea level rose permanently by 1.5mm as a result. 
As Scambos said, “we are crossing thresholds not seen in millennia, and frankly this is not going to change until we adjust what we’re doing to the air”.