NSIDC, August 18
Rain was observed at the highest point of the Greenland Ice Sheet for several hours on August 14, with air temperatures above freezing for about nine hours total. There is no previous report of rainfall occurring at this location, which reaches 3,216 meters (10,551 feet) in elevation. This was also the latest date in the year on record that the U.S. National Science Foundation’s Summit Station had above-freezing temperatures and wet snow; and the third time in less than a decade. Earlier melt events (but no rain) occurred in 1995, 2012, and 2019; before the instrumental record began at Summit Station in 1989, ice cores suggest just one previous melt event occurred in the late 1880’s. The cause of the overall melting event that took place from August 14 to 16, 2021, along with a similar event in late July was rapid incursion of warm air and moisture from the south.