In the middle of the Greenland Ice Sheet, between Upernavik in the west and Scoresby Sound in the east, lies Summit Station at 3,216 metres above sea level. This makes it the highest, year-round station in Greenland. Of particular interest here are the meteorological measurements, especially now in the context of climate research. Because actually the climatic and atmospheric conditions for measurements should be stable here. But in recent years, the station has repeatedly reported warm spells and even massive melting events. But what was measured on August 14 was an unprecedented event: rain!
As reported by the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado (USA), rain fell for several hours and the air temperature remained above freezing for about nine hours. Since rain had never occurred at this location before, there were no suitable measuring devices for the amount of rain. As a result, no information on quantities could be provided.
According to the NSIDC, the reason for the extreme weather was the same as for the big melting event a few weeks earlier: A low-pressure area over the west side of Greenland up to Baffin Island and a high-pressure area over the southeast coast of the island let warm and very humid air flow to the north. On the one hand, this caused the temperature in the middle of the island to rise relatively quickly to such an extent that rain fell instead of (wet) snow. Experts estimate that a total of about 7 billion tons of water had poured over Greenland.
This is the third time in 10 years that researchers had measured plus degrees at Summit Station. The other two times were in 2012 and 2019. Before that, they had only been detected by gauges in 1995 and, in one case, by data from ice cores showing it in the late 19th century, the NSIDC says. At times the temperature was 18°C above the long-term average in parts of Greenland and caused large parts of the ice sheet to melt again.
Dr Michael Wenger, PolarJournal
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