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COPENHAGEN: Temperatures in parts of Greenland are warmer than they have been in 1,000 years, the co-author of a study that reconstructed conditions by drilling deep into the ice sheet said on Friday.
“This confirms the bad news that we know already unfortunately — (It is) clear that we need to get this warming under control in order to stop the melting of the Greenlandic ice sheet”, climate physics associate professor Bo Mollesoe Vinther of the University of Copenhagen said.
By drilling into the ice sheet to retrieve samples of snow and ice from hundreds of years ago, scientists were able to reconstruct temperatures from north and central Greenland from the year 1000 AD to 2011.
Their results, published in the scientific journal Nature, show that the warming registered in the decade from 2001-2011 “exceeds the range of the pre-industrial temperature variability in the past millennium with virtual certainty”.
During that decade, the temperature was “on average 1.5degrees Celsius warmer than in the 20th century”, the study found.
The melting of the Greenland ice sheet is already leading to rising sea levels, threatening millions of people living along coasts that could find themselves underwater in the decades or centuries to come.
Greenland’s ice sheet is currently the main factor in swelling the Earth’s oceans, according to Nasa, with the Arctic region heating at a faster rate than the rest of the planet.
In a landmark 2021 report on climate science, the Intergovernmental Panel on Climate Change (IPCC) said the Greenland ice sheet would contribute up to 18 centimetres to sea level rise by 2100 under the highest emissions scenario.
The massive ice sheet, two kilometres thick, contains enough frozen water to lift global seas by over seven metres in total.
Under the Paris climate deal, countries have agreed to limit warming to well under two degrees Celsius.
“The global warming signal that we see all over the world has also found its way to these very remote locations on the Greenland ice sheet”, Vinther said.
“We need to stop this before we get to the point where we get this vicious cycle of a self-sustaining melting of the Greenland ice,” he warned.
Huge ice sheet
The total area of Greenland is 2,166,086 square kilometres, of which the ice sheet covers 1,755,637 sq.km — roughly 80 per cent of the total. The ice sheet has a volume of approximately 2,850,000 cubic kilometres.
The weight of the ice sheet has depressed the central land area to form a basin lying more than 300 metres below sea level, while elevations rise suddenly and steeply near the coast.
The ice flows generally to the coast from the centre of the island. A survey led by French scientist Paul-Emile Victor in 1951 concluded that, under the ice sheet, Greenland is composed of three large islands.
This is disputed, but if it is so, they would be separated by narrow straits, reaching the sea at Greenland’s Grand Canyon and south of Nordostrundingen.
Published in Dawn, January 21st, 2023
