March 1, 2013. Recently, the inhabitants of the earth began to notice what became frequent and powerful weather events. Everyone remembers the hot summer of 2010 when drought and fires have covered many regions of Russia. Record heat is regularly in Europe and in the United States and Japan, replaced by unprecedented rains and cold weather, turning into the flood.
So different at first glance, the events are unlikely to be a coincidence. The same was said and the new work of an international group of climate scientists, including Professor and the German Institute of PIK Vladimir Petukhov. In an interview PublicPost scientist explained how and why the climate system runs away.
Vladimir Petukhov, "Extremely hot and cold spells, which we observe in the summer in recent years, trying to explain a few theories. They offer different mechanisms of why over this or that region is set, and most importantly — delayed and amplified region of high or low temperature.
Such anomalies can be delayed for months, and at the same time manifest itself in different, separated by great distances, areas. After all, for example, heat in Russia in 2010 was accompanied by an equally unusual weather over India and Pakistan. In the summer of 2012, the observed alternation of extreme temperatures — hot, cold — both in the United States, southern Europe, China and Japan.
So we looked at the global picture of the circulation of air over the mid-latitudes of the northern hemisphere. We compared what is happening in these "extreme years," so what is observed in normal years, which, fortunately, is still too happen.
It turned out that such anomalous periods in temperate latitudes of the troposphere at a height of 6-7 kilometers formed wave, alternate along the circle of latitude areas of heat and cold. She remains motionless, stretched 2.5-5 thousand kilometers, and even under these sections below on the surface of the earth, establish relevant, low and high, or temperature. These waves do not move either to the north or to the south, where they can dissipate their energy: they are sandwiched between the global jet streams, air jets.
These jets work and under normal circumstances: in the tropics at the same altitudes in the troposphere blow sufficiently strong easterly flow covering all full circle of latitude. Toward the north, somewhere in the 35-degrees, they move to the strong westerly winds. Then, over the mid-latitudes, sharply weakened and again reach the peak is closer to the polar regions. This is a normal pattern.
However, in recent years, global jets over the tropics increases sharply, wind may reach 15-20 m / s. And increases the power of the circumpolar flow. But the gentle breeze over the mid-latitudes is weaker sometimes almost doubled and can not gain more than 3-4 m / s. The result is a deep "energy well": in the south — a strong stream, then the failure — and again a sharp rise.
Here tall waves are locked and can not dissipate either north or south, staying motionless in the middle latitudes. At the same source that feeds their energy — solar radiation — remains in effect, and wave accumulate more and more power.
At this start to react and lower layers of the atmosphere and the surface of the Earth. Here, too, the temperature generated waves that are identical to the high-rise on the length and phase. And they both come into resonance and reinforce. None of them can not dissipate the stored energy — and both are growing.
That's when we observe the simultaneous appearance and abrupt alternation of heat and some areas of extreme cold in others, as it was in 2010 in Moscow and Pakistan who share just half of a high-altitude wave length of about five thousand kilometers.
Of course, the perfect wave, and we have a strict alternation watch can not, because everywhere the important role played by regional characteristics and random vibrations: the humidity somewhere, somewhere proximity of the ocean … However, the picture is quite specific, and it can be confidently associated with global warming.
After all, this warming is not happening evenly everywhere, everywhere a different response to it. Mid-latitudes have larger mass of the ocean, which has a high heat capacity and reacts slowly. It does not allow them to heat as rapidly as in the Arctic or subtropical areas.
As a result of the global jets in the north and south of the accelerated and amplified, and between them — even more weakened. "Energy Well" deepens and wave is trapped in it, turning to temperature anomalies, which we will probably have to get used to now. "