By comparison, between 2003 and 2016, the ice sheet lost an average of about 255 billion tons of ice – per year.
“We have documented another year for record loss for Greenland,” said Ingo Sasgen, a glaciologist at the Alfred Wegener Institute for Polar and Marine Research and co-author of the study.
“What this shows is that the ice sheet is not only out of balance, but it is increasingly likely to produce more and more extreme loss years.”
Greenland, an autonomous territory of Denmark, is the largest island in the world. It lies between the Arctic and Atlantic Oceans, east of the Arctic archipelago of Canada. About 79% of its surface is covered with ice.
Greenland’s ice sheet is the second largest in the world behind Antarctica, and its annual summer melting ice contributes more than a millimeter to sea level each year.
But that is set to decrease as increasing greenhouse gas emissions warm the planet.
“We are seeing an Arctic heat up about one and a half times faster in the summer compared to the global average,” Sasgen said.
In 2019, the Greenland ice sheet lost 15% more ice than the previous record set in 2012, the study found. And although the ice sheet has been melting more and more since the 1990s, according to the report, several circumstances led to the record melting in 2019.
Sasgen said that these ever-increasing temperatures combined with low snowfall, and warm atmospheric and cloudless conditions that let more solar radiation into the ice sheet, led to the enormous melt production seen last year.
Interestingly, two colder years that preceded 2019 saw a reduction in ice melt. Satellite data found that Greenland’s ice loss in 2017 and 2018 was lower than in any other two-year period between 2003 and 2019, due to two abnormally cold summers in western Greenland, a snowier fall and winter conditions in the east, according to the report.
However, Sasgen said these two cold years do not compensate for the dramatic meltdown in 2019. The report found that the ice sheet will continue to lose mass in response to Arctic warming.
“This extreme meltdown throws up feedback that can accelerate mass loss. This is something that is worrying, the extremes are increasing and we understand too little about how the ice sheet will respond to more extreme climate variability,” Sasgen said.
Reducing CO2 levels, Sasgen said, is the only hope to slow global warming and reduce future extreme ice melt.
Just as we think of the Romans as the civilization that plagued the sewer system, Sasgen said we need to consider how our society will be conceived in the coming years.
“If you think about our civilization in 2000 years when the ice sheet has shrunk significantly and the sea level has risen by probably a few meters, then our society will be considered as the one that caused this decline in the continental ice triggered, “he said.
“It’s not just four years, like 10 years or 100 years, it’s a process that will go on for a very long time and we’re just seeing the beginning of it.”
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