In Longyearbyen, the mercury rose to 21.7 degrees Celsius last weekend.
That may not seem very impressive. But for Longyearbyen – the largest settlement on Spitsbergen – it is really a new heat record.
Temperatures in the northern town are quite low even in summer. The last time temperatures even came close to last weekend’s heat record was in 1979. On July 16 of that year, the mercury rose to 21.3 degrees Celsius. A heat record that lasted for decades, but died last weekend.
The heat record of last weekend was set during a real heat wave. The temperature in Longyearbyen has been above 20 degrees Celsius for several days in a row. “The high temperatures are caused by a warm air mass that comes from the south and southeast and can be traced to a powerful high-pressure area in the Arctic,” climate researcher Mika Rantanen, of the Finnish Meteorological Institute, tells Scientias.nl . “Furthermore, the lack of sea ice in the Arctic seems to have given the heat an extra boost (see box, ed.).”
Researchers have known for a long time that melting sea ice can have a huge impact on the (local) temperature. In fact, it is one of the best-known feedback processes: processes in which warming leads to more warming. When the Arctic sea ice melts – due to the warming of this northern area – the underlying dark ocean is exposed. And where the sea ice previously reflected sunlight and heat, the dark ocean absorbs sunlight and heat. And that leads to even more warming. So the consequences of this feedback process are now being experienced in the Arctic Circle.
The heat record set in Longyearbyen is not an isolated one. For example , a heat record had already been broken in Siberia . In June – after a months-long period of unusually high temperatures – a record temperature of more than 38 degrees Celsius was measured. “The heat in Siberia is clearly related to anthropogenic climate change,” says Rantanen. “And this heat wave (in Svalbard, ed.) Is really just a continuation of the Siberian heat. The entire Arctic region is now very warm, due to the lack of sea ice, which (through the feedback process described above) can lead to even higher temperatures in the entire Arctic region. ”
Sign on the wall
And so the heat record that has been set on Spitsbergen can therefore be a sign on the wall. “Extremely high temperatures will indeed occur more and more in the future due to climate change,” says Rantanen. “The more the planet warms up, the more often we will see these extreme events. Certainly in the Arctic that warms up much more than the rest of the earth does on average. In that sense, you could say that this (the unusually high temperatures on Spitsbergen, ed.) Is the ‘new normal’. ”
Little bright future
It is in line with a report released last year that outlined a less rosy future for Spitsbergen, which has the dubious honor of being called the fastest warming area on Earth. Today, the average temperature in winter is about 7 degrees Celsius higher than in 1971. It means very specifically that Spitsbergen has lost about two winter months in the past five decades. The average annual temperature has risen about 4 degrees Celsius in the same period. For comparison, the average global temperature has increased ‘only’ by 0.87 degrees Celsius since 1971. And if we do not cut our emissions significantly, the average annual temperature in Spitsbergen may be 7 to 10 degrees Celsius higher by the end of this century. this is how quaternary geologist Wim Hoek concluded earlier . Species that rely on sea ice – think ringed seals, polar bears and ivory gulls – are in trouble. The same goes for reindeer that risk starving in the milder winters.
“And the changes in permafrost, precipitation, sea ice, snow and glaciers will also affect the inhabitants of Spitsbergen,” Hoek said.
Spitsbergen is not only the fastest warming area on earth. It is also where the Global Seed Vault is located: a huge vault filled with thousands of seeds. This World Seed Bank serves as a kind of insurance policy. Even if the more than 1700 seed banks worldwide lose their seeds due to technical defects – a broken freezer – or real natural disasters or wars, seeds of the same species are still stored on the politically stable Spitsbergen, hidden deep in permafrost. But is that World Seed Bank on Spitsbergen as untouchable as expected, now that the area is heating up at lightning speed? In 2017, melting permafrost already caused leakage and adjustments had to be made to protect the World Seed Bank and the seeds it houses. Still argues Nordic Genetic Resource Center , manager of the World Seed Bank, does not expect climate change to threaten the seed vault.
For many people, the summer of 2020 will go differently than expected due to SARS-CoV-2. But even in the Arctic, summer – for quite different reasons – is still quite bizarre. One heat record after another breaks down. First in Siberia, then in Longyearbyen. And also in Canadian Eureka, almost the most northerly inhabited place on earth, an old heat record was broken this weekend, when the mercury rose to 21.9 degrees Celsius. The high temperatures do not put the sea ice in the cold clothes either; satellites have never seen so little sea ice in the Arctic at this time of year.