Published on 20 August 2021
Every year from around May to early September, melting takes place across the vast sheet of ice that covers Greenland. Besides contributing directly to sea level rise, meltwater can flow to the base of the ice sheet via crevasses and moulins, accelerating the flow of ice toward the ocean.
Within a melting season there can be the occasional “melt event”—brief periods with more melting and runoff than during ‘typical’ summer days. The seventh-largest melt event on record (by area) occurred on July 28, when melting covered about 881,000 square kilometers (340,000 square miles) of the ice sheet, according to data from the National Snow and Ice Data Center. Melting on August 14—the peak of the unusual late-summer event—was slightly smaller, covering about 872,000 square kilometers.