Still very strange thing that global warming: someone from him hot, and someone - on the contrary. Here and scientists from the U.S. he is linked abnormally cold winters of recent years that regularly froze residents of the Northern hemisphere. More specifically, with very rapid melting of Arctic glaciers, the reason of which is the global warming.

It looks like the weather in the Northern hemisphere of our planet have decided to completely ignore the very global warming, which is already several years, researchers say. Abnormally cold winters of recent years in Europe and North America, as if, they try to prove the opposite. Actually, oddly enough, no contradiction here. Although direct connection.

In fact, if you look closely, anomalous cold last winters are not global and local. For example, in the beginning of 2011 in the US and Europe lashed by severe frosts, although in Greenland and Alaska was unusually warm. In the same year, in late winter in the US and Europe, in contrast, was even hot (in March), while Central Europe and North Asia have got a much less severe cold lasted somewhere until mid April.

So, as you see, there is a kind of weather mosaic: in one region is bitter cold, and next to him is abnormal warm. All this suggests that such volatility weather in the winter months is the result of the impact of not one but several factors. However, it may be behind the phenomenon? Let's try to understand.

Strictly speaking, mostly weather in the Northern hemisphere is associated with the so-called Arctic oscillation - periodic variation of surface air pressure and the associated change of wind direction. In this oscillation there are two phases - negative and positive. During the positive phase of strong winds known as the polar vortex. Because it ' machinations" Arctic air masses are blocked in the area of the pole and does not reach the middle latitudes. Thanks to this phenomenon jet stream atmosphere become more direct, and, accordingly, the winter is issued more moderate.

Another thing negative phase - during it the winds of the polar vortex weaken, the vortex practically disappears and in the Arctic air begins to spread from pole to temperate latitudes. Moreover, the cold polar masses are mixed with those of middle latitudes, which is significantly warmer. This is all rather weakens the jet stream, which, moreover, become strongly deviate from its normal route on the North and the South. This leads to the severe cold weather in the US and Europe during the winter months.

Now, according to recent observations in recent years oscillation was in the negative phase. We can say that in sharply negative in the same 2010 and 2011 were registered record low winter temperatures in many regions of the Northern hemisphere. And this despite the fact that according to calculations of scientists, the negative phase had already ended by that time. However, it somehow lingered and in the near future will scare us winter frosts.

Specialists climate for a long time tried to find an explanation for this strange delay. And now a group of researchers from Cornell University (USA) proposed an interesting hypothesis. They believe that this anomaly can be connected with another overly rapid and large-scale melting of Arctic ice, which is observed since the beginning of this century.

This Association, according to climatologists, is not direct. Everyone knows that during the summer the open ocean absorbs much more sunlight than before. And the Arctic ocean is no exception to this rule. In the autumn he returns the part of the heat produced in the atmosphere, warming the air over the Arctic. Obviously, this amount of heat directly depends on the area of accumulating the surface of the open water surface.

Well, because of ice in the Arctic has become much less, increased surface area of the ocean, courtyard during the summer months, and, consequently, the stock of accumulated heat the water column. And in the autumn it because it stands out a lot more. This heat prevents the formation of the polar vortex and thus forced to delay the Arctic oscillation in the negative phase, which, in turn, weakens the jet stream and brings in the Northern hemisphere cold winter.

In order to prove his hypothesis, the researchers studied the charts of the Arctic ice melts with the moment in the Northern hemisphere have begun satellite observation (that is, 1979). Eventually it was revealed that since that time the ice is slowly melting until 2007, when there was a sharp reduction in the area of Arctic glaciers. And now, after, except for the pause" in 2009, it decreased rapidly.

Further, the climate scientists have analyzed schedule phase of the Arctic oscillation. And what do you think - we found lot of matches. In particular, in 2006 ended in positive phase and came negative. The idea is that it was supposed to be completed by 2010, but due to the rapid melting of the ice, this has not happened. In the end, still the inhabitants of the Northern hemisphere suffer from abnormally low winter temperatures.

Well, with cold winters seems clear enough. And why in some areas came abnormal spring fever? Climate scientists attribute this to the influence of several factors. For example, the March of the current heat in the U.S. was due to the fact that due to the weakening of counter jet streams warm southern air masses were able to move far to the North. Eventually warm the air, carried by the current La Nina in the South Pacific, and has caused quite a hot March.

Well, it turns out that the abnormally cold winter of the Northern hemisphere really indirectly linked to global warming, because of which the Arctic ice started to melt faster than necessary. Agree, the strange thing is warming: someone from him hot, and someone - on contrary...

Anton Evseev