Friday, August 20, 2021

Rain falls on Greenland's normally snowy summit for the first time on record

Emily Chung 12 mins ago
© Saul Loeb/Pool/The Associated Press Areas of Greenland are seen from the air on Thursday, May 20, 2021. Greenland saw an unprecedented weather event this week, when rain fell on its normally snowy summit for the first time on record.

For the first time on record, rain has been recorded on the summit of Greenland — a location where precipitation has previously always fallen as snow or ice.

"There is no previous report of rainfall at this location (72.58°N 38.46°W), which reaches 3,215 metres in elevation," reported the U.S. National Snow and Ice Data Center of the Aug. 14 event.

The rain began at 5 a.m. local time (3 a.m. ET) that morning, and was photographed by Alicia Bradley, the science technician at the National Science Foundation Summit Station, an hour later.

She and Zoe Courville, a polar engineer and snow scientist, were credited with the observation.

Temperatures peaked at 0.48 C at 8:40 a.m. local time.

It's only the fourth time the temperature has been recorded above freezing at that location. But in the previous instances in 1995, 2012 and 2019, there was no rain. Before that, the last record of above-freezing temperatures, based on ice cores, was in the 1880s.

The rain was accompanied by a massive ice melt of 872,000 square kilometres on Aug. 14.

Only two other melts, including one earlier this year (the other was in 2012), have been over 800,000 kilometres, and this is the latest in the year it has ever occurred, the NSIDC said.
Ice melts can lead to flooding

That led to massive loss of surface mass from Greenland's ice sheet — seven times higher than the mid-August average.

"At this point in the season, large areas of bare ice exist along much of the southwestern and northern coastal areas, with no ability to absorb the melt or rainfall," the report noted. "Therefore, the accumulated water on the surface flows downhill and eventually into the ocean."

Melting ice sheets in Greenland and Antarctica are expected to be the main contributors to sea level rise — an impact of climate change that can lead to dangerous and costly coastal flooding worldwide.

Studies in 2020 found the rate of melt matched the UN's Intergovernmental Panel on Climate Change's worst-case climate warming scenario, and Greenland's ice cap is melting faster than it has in 12,000 years.

The melt in Greenland and Antarctica could also have a major and underestimated impact on extreme weather in Canada, a 2019 study found.

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