Climate scientist and glaciologist Ruth Mottram of the Danish Meteorological Institute took to Twitter on Thursday to share the sobering news that Greenland lost 11 gigatons of ice in a single day on Aug. 1.
A gigaton is a billion metric tons. "A single gigaton of water would fill about 400,000 Olympic-sized swimming pools," NASA said in an ice explainer in 2018.
NASA satellites have been watching the hot weather unfold and take a toll on Greenland's ice sheet in July. "Billions of tons of meltwater streamed into the Atlantic Ocean throughout the month, making a direct and immediate contribution to sea level rise," the agency said in a release on Friday.
An image captured by the Landsat 8 satellite shows how the meltwater is creating ponds near the edge of the ice sheet.
"Summer melting along the periphery is typical," said NASA. "In contrast, a melt area that totals nearly 1 million square kilometers of the ice sheet, as it did on July 30-31, is less common."
The view from ground level is also sobering. Writer Laurie Garrett shared a video Thursday showing glacial meltwater roaring under a bridge in Greenland.
We already had a clue back in June that 2019 would be a brutal year for Greenland. A climate researcher shared an image of water that had melted off from a layer of sea ice near an Arctic village. That photo went viral.
Greenland's last major melt event happened in 2012. It may not take seven years to reach the next one.