Arctic ice levels, August 2012
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The National Snow and Ice Data Centre in the USA confirmed that data presented by its Japanese colleagues show that Arctic sea ice shrank to its lowest point since satellite records began in 1979, down to 4.1 million square kilometres (1.58 million square miles) in August. This is 70,000 square kilometres (27,000 square miles) less than the previous record low set on 18 September 2007. Foreign experts forecast that by 2040, the Earth’s ice cap might disappear, but Russian scientists disagree with these pessimistic forecasts. Experts from various countries are closely monitoring the state of the Arctic sea ice because this region is the “weather kitchen” of the planet. Since 1979, they’ve used satellite images, but applied different methods to assess the area covered by ice. Scientists from the Arctic and Antarctic Scientific Research Institute (AANII) in St Petersburg are leaning on rich experience gained by field studies, which foreign experts don’t have.
Dr Genrikh Alekseyev said, “The findings show that the Arctic sea ice is ‘renewing’ itself; this is a seasonal change, it’s not the disappearance of the icepack. The reason is that in the summer, the ice melts, whilst in the winter, ice is formed. Practically, the area covered by winter ice shrinks very slowly. In the winter, the ice layer is restored. However, this concerns especially newly-formed ice in the process of formation, and, by next year, its thickness can reach up to 1-metre (@40 inches) or more”.
In winter, the newly-formed ice actively can form a 1.2-metre (@47 inches)-thick layer, whilst the coastal ice can grow up to 2.0 metres (79 inches). Consequently, the Arctic sea ice layer doesn’t change significantly. Moreover, according to Dr Alekseyev, in the summer, ice melts seas unequally in different places. This year, the seas through which the Northern Sea Route passes were covered with an unusually-thick ice layer. A thin ice layer covered the Barents Sea, but the amount of ice in the Kara, Laptev, East Siberian, and Chukchi Seas exceeded the level of 2007. The conditions in the Arctic in a warm summer can be considered abnormal, but the Northern Sea Route hasn’t been completely freed from ice yet. Dr Alekseyev noted, “This means that we’d still need icebreakers in future. According to forecasts made by using calculations on global models, by the end of the century, ice might disappear almost completely in the summer, but ice will be formed up to the previous borders in the winter”.
The extreme melting of ice in the summer 2012 is most likely the last sign that the warming is ending. In fact, ice is a product of climate, and Dr Alekseyev pointed up that when you compared the graphs of the air temperature and melting ice, one can see that they coincide. The long-term monitoring by experts at the institute confirmed the presence of a 60-year climatic fluctuation cycle, where reorganisation of atmospheric processes and the circulation of oceans related to them take place. At present, according to their calculations, another period of warming is ending, whilst the previous warming peak was registered between 1930 and 1940. We only know the nature of these cycles in a vague way, and scientists are still unaware of many of the natural processes of the oceanic environment.
31 August 2012
Maria Domnitskaya
Voice of Russia World Service
http://english.ruvr.ru/2012_08_31/Arctic-sea-ice-rejuvenating/
