For weeks there has been exceptionally little ice on the ocean near the North Pole, according to satellite images. Not before since the beginning of the measurements there was so little sea ice in October. The disappearance of the ice has a major impact on the Arctic ecosystem, according to a recent study.
Normally, the sea ice grows strong in the months of October and November, after the amount of ice reaches the annual minimum in September at the end of the summer.
The size of the Arctic lice did not reach a low record in September, in the more than 40 years of satellite measurements. Only in 2012 there was even less ice. But then the ice grew faster in the autumn than it is now.
Heat wave Siberia
That this is so slow this year is partly because Siberia was struggling with a big heat wave in the summer. As a result, the sea water in Siberia is still warmer than normal.
According to the weatherman and climate scientist Peter Kuipers Munneke, the moment when the North Pole is completely ice-free in part of the year is quickly approaching. “Over the past forty years, three-quarters of the sea ice has disappeared. If this trend continues, the North Pole will be ice free in 14 to 15 years. It can also take 20 or 25 years, but most Dutch people who live now will still experience that.”
The melting of sea ice has a great impact on the ecosystem in the Arctic region, is stated in the study that appeared in Nature. Jacqueline Stefels of the University of Groningen participated in this research. When the ice disappears, the sunlight is no longer reflected by the ice, she says, but shines directly on and into the water. As a result, there will be more algae growth.
On the one hand, this is a positive development, says Stefels, because the algae serve as food for other species in the sea. On the other hand, it will eventually lead to very different animals than in the Arctic.
“ What you expect is that more Atlantic species will move north and that the entire ecosystem of the Arctic will collapse,” says Stefels. In the end, this has negative consequences not only for polar bears, but also for whales, seals and birds, for example.
Sare for a moment
Stefels was the only Dutchman to ride this year with a special Arctic expedition called Mosaic. The purpose of this was to freeze the German research vessel Polarstern at the North Pole, so that the same ice could be followed and examined for a year. Scientists from 20 countries travelled with different expertise. It was an exciting journey, says Stefels, especially because the ice was much less stable than expected when she was staying on the ship.
Computer calculations had indicated that the ice would be thicker, and less dynamic. “We were just there a week and the place is breaking open. And we see that the ice is going to slide, anchor lines that snap. People are immediately recalled from the ice. That was a bit of a scare.”
In the winter there will be sea ice at the North Pole for the time being, thinks Stefels. But the current situation, as the ice grows so slowly after the summer, calls it alarming. She hopes that the world will soon emit far fewer greenhouse gases, “then some of the sea ice can be saved”.
Sea level rise
The disappearance of this ice does not lead to a rise in sea level. It floats at sea, and when it melts, the sea level stays the same. But it does ensure that the area warms up even faster because the sun will shine directly into the water.
Kuipers Munneke: “Near the sea ice there are many large glaciers, such as Greenland, Nova Zembla, Spitsbergen and Canada. And if the Arctic heats up further, that ice will also partly melt, and that will contribute to a rise in sea level.”
By the way, both he and the KNMI suspect that the disappearance of sea ice will also have consequences for the weather in Western Europe. But it is still unclear what exactly those consequences will be.