Greenland is melting in a heatwave. That’s everyone’s problem

CNN  — 

Extreme heat bowled over Europe last week, smashing records in its wake. Now, the heatwave that started in the Sahara has rolled into Greenland – where more records are expected to crumble in the coming days.

That means the heatwave is now Greenland’s problem, right? Not quite. When records fall in Greenland, it’s everyone’s problem.

Greenland is home to the world’s second-largest ice sheet. And when it melts significantly – as it is expected to do this year – there are knock-on effects for sea levels and weather across the globe.

Greenland’s ice sheet usually melts during the summer. This year, it started melting earlier, in May, and this week’s heatwave is expected to accelerate the melt.

The country’s mammoth ice sheet rises 3,000 meters above sea level. Forecasters predict that its summit will be particularly warm this week, at just below zero degrees.

“It’s a very warm temperature for that altitude,” said Ruth Mottram, climate scientist at the Danish Meteorological Institute.

Now 2019 could come close to the record-setting year of 2012, said Jason Box, professor and ice climatologist at the Geological Survey of Denmark and Greenland. During that “melty year,” he said, Greenland’s ice sheet lost 450 million metric tons – the equivalent of more than 14,000 tons of ice lost per second.

Global effects

What happens in Greenland will be felt across the world.

Box said that this year’s melt is flooding the North Atlantic with freshwater, which could affect the weather in northwestern Europe. The result could be stronger storms, he added, citing flooding in the UK in 2015 and 2016.

“Whatever happens in Greenland radiates its impact down,” he said.

Vehicles in a flood caused by rising sea levels on a highway in Central Java, Indonesia on February 2.

During a year like 2012 or 2019, water produced by Greenland’s ice sheet adds more than one millimeter to global sea levels, according to Box. But countries in the tropics could see a rise of two millimeters or more, he said.

Extreme is the new norm

It will still be some time before the full “meltiness” of 2019 is measured. But it’s already poised to rival the proportions of 2012 – and we haven’t even reached the end of summer.

In July alone, Greenland’s ice sheet lost 160 billion tons of ice, according to Clare Nullis, spokeswoman for the UN World Meteorological Organization. That’s roughly the equivalent of 64 million Olympic-sized swimming pools, she told reporters on Friday.

One of the most remarkable things about the 2019 heatwave is not just the number of records it broke across Europe – but the margin by which it did so, she said.

“Normally when you get a temperature record broken, it’s by a fraction of a degree,” said Nullis. “What we saw yesterday was records being broken by two, three, four degrees – it was absolutely incredible.”

And it’s not just the heat that’s breaking records. Last year, Greenland experienced it’s coldest year in decades, said Box.

Visitors interact with blocks of melting ice from an exhibit called 'Ice Watch' in central London in December 2018.

According to Nullis, intense heatwaves such as the one bringing up temperatures in Greenland “carry the signature of man-made climate change.”

It’s a view shared by a group of European scientists, including scholars at the University of Oxford, who earlier this month concluded in an analysis published in World Weather Attribution that recent French heatwaves had been made five times more likely because of climate change.

The researchers also said that the world is “very likely” to see more extreme heatwaves in the future due to climate change.

CNN’s Isabelle Gerretsen contributed to this report.