Abnormal frosts in Central Europe — a consequence of reduction of the area of summer Arctic sea ice, the authors of the study published in the journal Tellus A Wednesday.
According to German scientists from the Institute of Polar Research Alfred Wegener (AWI) and the Helmholtz Research Center of the Earth (GFZ), heating the air from the waters of the Arctic Ocean increases the vertical circulation, because the warm air mass rises, being replaced by colder. As a result, the lower atmosphere are unstable and seasonal "scheme" of the distribution of atmospheric pressure changes in the Arctic and North Atlantic, RIA "Novosti".
One of the well-established systems of atmospheric pressure, which is suffering because of it — the so-called Arctic Oscillation to seasonal Azores high and the Icelandic low. In cooperation with each other, they create a gradient, and if the difference in pressure is high, formed a strong west wind, which brings out the warm Atlantic air masses. This flow, releases moisture mountainous Central Europe, provides a warm and snowy winter. If the air flow is not formed, then to Europe gets cold and dry air from the Arctic, as it did the last two years.
Calculations of scientists have shown that the difference in pressure between the Azores high and the Icelandic Low reduced in those years when the Arctic is melting more ice.
Scholars have identified two mechanisms in the Arctic warming near the surface of the water layer of the atmosphere, both the process started by the melting ice. First, the ice retreated, leaving all the large areas of open water, which, in contrast to the bright surface of the ice with a high albedo — reflectivity measure surface absorbs solar radiation and heats up. Then, with the onset of the cold season, give it water masses of warm air. In addition, the fall and winter ocean, devoid of sea ice shield, gives off heat to the atmosphere. Such large-scale climatic phenomenon in the Arctic called the "effect lifted the lid," the report said.
Scientists emphasize that their study describes the mechanism of climate in general, and therefore, there may be seasonal and regional exceptions caused by other factors, the formation of weather.
"Our work aims to study the regional climate scenarios, given the global processes … This should help people to gradually adapt to climate change "- are reported to head of the atmospheric circulation AWI, Professor Klaus Dethloff.