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Sea ice breaks in the spring. Near Kulusuk, Greenland.
(steve_is_on_holiday / Getty Images)
- Only about 20% of the sea ice completes their typical journey in the Arctic before melting.
- Two decades ago, 50% of newly formed sea ice completed their journey.
Due to global warming, only about 20% of sea ice born in the shallow seas of Russia exceeds the "nursery" without melting, says a new study.
Two decades ago, more than 50% of newly formed sea ice made a long trip from the nursery located off the Arctic coast of Russia to the central Arctic Ocean. There, he joins the trans-polar drift and leaves the Arctic towards the Greenland Sea by the Strait of Fram, between Greenland and Svalbard. Today, 80% of the ice melts before the end of the trip, according to a study published Tuesday in Scientific Reports.
Considered as the "nursery" of the Arctic sea ice, the shallow marginal seas of Russia – the Barents Sea, the Kara Sea, the Laptev Sea and the East Siberian Sea – are constantly producing new sea ice during Winter due to extremely low temperatures that can go down to minus 40 degrees Fahrenheit.
A strong sea breeze propels the newly formed ice towards the center of the Arctic Ocean, where it is washed away by the transpolar drift. In two or three years, the ice finally enters and leaves the Fram Strait, where it usually melts. Today, only about 20% of the ice floes through the journey.
The shallow Russian coastline or the marginal seas of the Arctic Ocean are generally considered to be the "nursery" of Arctic sea ice: in the winter, the Barents Sea, the Kara Sea, the Laptev Sea and the East Siberian Sea. constantly produce new sea ice.
(Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research)
Researchers from the Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, say the findings suggest that the world is on the verge of making ice-free summers in the Arctic.
The researchers came to their conclusions using satellite data from 1998 to 2017 to monitor and analyze the movements of sea ice.
"Our study shows extreme changes in the Arctic: melting sea ice in the Kara Sea, the Laptev Sea and the East Siberian Sea are now so fast and so widespread that we are witnessing a lasting reduction in the amount of new ice for transpolar drift, "writes lead physicist Thomas Krumpen, ice physicist at the Alfred Wegener Institute, said in a press release.
Krumpen notes that the ice that reaches the Fram's straight line is now forming in the open waters of the central Arctic Ocean rather than in marginal seas.
"We are witnessing a major transport movement that is wavering, bringing the world closer to a summer without ice in the Arctic," he said.
(MORE: Canadian island affected by thousands of landslides due to melting Arctic permafrost)
In general, ice formed along the Russian coast collects important nutrients, algae and sediments and transports it to the Arctic. With the formation of more ice in the central Arctic, fewer nutrients, algae and sediments are being transported, which could permanently alter biogeochemical cycles and ecological processes in the Arctic. Arctic Ocean, the researchers said.
In addition, the ice that comes out of the Fram Straight is 30% thinner than it was 15 years ago.
"The reasons: on the one hand, the rise in winter temperatures in the Arctic and a melting season that starts now much earlier, on the other hand, this ice is no longer formed in the seas of the plateau, but much more to the north, has much less time to drift into the Arctic and turn into a thicker pack ice, "said Krumpen.
Thinner ice also means that it moves faster on the transpolar drift. The researchers had hoped that the acceleration would offset the decline of the ice, but this new study suggests that the ice melts too quickly to compensate for the increase in its speed.
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