Arctic Ocean will have approximately 10 years to clear the ice for one summer season, says Edmond Hansen of the Norwegian Polar Institute.
He and his colleagues from 1990 to 2010 carried out observations of ice thickness in the Fram Strait (between Greenland and Spitsbergen) using dive to the bottom sonar — sonar. Data collected by scientists indicate that the thickness of multi-year ice gradually decreases and approaches the thickness of one-year.
"The thickest ice is almost gone, and the thickness of old ice closer to the thickness, the typical first-year sea ice. We are approaching a state in which the conditions are quite favorable for most of the Arctic sea ice had time to melt in one summer," — said in the announcement for the performance of Hansen at the seminar on October 19, published on the website of the institute.
Researchers collected data show that since 2005, the thickness of multi-year ice in the Fram Strait decreased by 35%. If in the 1990s, the average thickness of multi-year ice in the late winter of 3.4 meters, and in 2005 it dropped to 2.2 meters. According to researchers, this suggests that the equilibrium in the Arctic shifted to progressively reduce the power of the ice cover.
In particular, it is about reducing the proportion of hummocky ice. Extensive fields such ice thickness over five meters in 1990 accounted for 28% of the ice cover in the Arctic Ocean, but now they have almost disappeared.
Not so fast
Most scientists now agree that the ice in the Arctic could disappear in summer by the end of the XXI century. However, the director of the Main Geophysical Observatory named Vladimir Voeikova Kattsov in September 2010 stated that the drifting ice in the Arctic may disappear entirely during summer much earlier — not the end, and in the second half of the XXI century.
The head of the climate program of WWF Russia Alexei Kokorin in an interview with RIA Novosti said that the withdrawal of the disappearance of ice in ten years makes him wonder.
"From a scientific point of view, this simply can not be. Never a moment when we watch satellite — and the ice is not — this is not possible a few decades," — said Kokorin. He recalled that the calculations of scientists Main Geophysical Observatory named MGO and the Arctic and Antarctic Research Institute indicate that the situation might get to around 2060.
According to the expert, the reduction of the thickness of multi-year ice does not mean that the ice will disappear altogether.
"Perennial ice really is getting smaller. But we still have the Canadian Arctic where perennial ice still quite a lot. And this part is not touched until lightly. But even if we have all the ice is equal to the thickness of the first year, it does not mean that some point, the ice disappears altogether. After the ice and melts and freezes at the same time "- said Kokorin.
He speculated that it could be of absolutely no ice-free sea, and on the area where it can take a ship without an icebreaker. "The fact that the ice is so thin that you can go ice-class vessels without icebreakers, you can imagine. But then again, not every year. I would urge to take these findings (Hansen) with caution" — concluded Kokorin.
However, the reduction in the total ice area and the area of multi-year ice is a scientific fact.
In early October, the German scientists, who returned from a 16-week expedition vessel "Polarstern", said the multi-year ice in the central Arctic have almost disappeared, and their place was taken by "young," first-year ice. Where there used to be a relatively large multi-year ice thickness (from two to five meters), is now dominated by annuals thin thickness of about 90 centimeters.
Perennial sea ice expedition found only in the waters of the Canadian Basin and near the Severnaya Zemlya archipelago.
In March, experts from the National Information Center for Snow and Ice (NSIDC) U.S. reported that Arctic sea ice continues to "younger" in March 2011 to the ice age of about one to two years accounted for 80% of the total area of ice cover, while in 1980-2000 years, the figure was an average of 55%.
In this case, in September 2011, they stated that the area of ice came close to record low in 2007.