The rain actually came from what meteorologists call an “atmospheric river,” a narrow gorge of moisture at high altitudes, causing torrential rains in its wake. But we tend to watch the south a lot more. The combination of this unusually warm air and rain, at a peak indicating an altitude of 3,200 meters above sea level, pushed the snow-covered area back 700 meters and created a river that poured a record level of water. Just enough water to add a few days to the thawing season, which in Greenland usually comes to an end around August. And just enough snow has melted from that heat to expose the darker ice, which absorbs more of the sun’s rays rather than reflecting it back — increasing melt even more, and making it a bigger factor than rain, note the authors of the new analysis, sponsored by the Danish Geological Office and Greenland, Back in the magazine Geophysical Research Letters.

The fact that all this happened in an area that was studied throughout the year by a scientific station (“top station”) It attracted more attention from expertsIt was for this reason that the rain that surprised by its size, who was blamed first Last August for all that followed: it was the first time rain at this height had been recorded in Greenland.

The researchers suggest that a better understanding of these atmospheric rivers, whose meandering curves can span thousands of kilometers, may be more important than understanding rainfall, in predicting how fast Greenland’s ice sheet is. It will continue to melt.