Science
Author`s name Timothy Bancroft-Hinchey

Spring is shifted by a month by Polar cyclone

Who is to blame for the fact that March of this year in the European part of Russia was not a spring, but a typical winter month? Does it have anything to do with the unusually warm spring in the south of Siberia? Scientists suggest that this "weather mess" was caused by a circumpolar stratospheric cyclone in late winter that closely approached our continent.

A very atypical spring with heavy snowfall and cool temperatures in the European part of Russia and warm weather in Siberia again led to speculation that the Earth's climate has finally and irreversibly deteriorated. Some blame global warming (which seems to have turned into a planetary scapegoat), others blame the oil rig disaster in the Gulf of Mexico that supposedly "broke" the Gulf Stream, and others - an inversion of the magnetic poles of the Earth. In short, terrified people again began expecting the next end of the world. But is it really that scary? What do scientists have to say?
   

As expected, scientists once again urge not to rush into conclusions and panic. In fact, absolutely nothing terrible has happened. Indeed, if you look at satellite maps of the Gulf Stream regularly published by NASA on its website, you can see that the most powerful Atlantic warm current has not changed. As for global warming and the inversion of the magnetic poles, the researchers once again remind us that this is a very long and slow process, whose effect will be noticeable only in a few decades (or even hundreds of years). Incidentally, these processes are not irreversible.
 

In addition, people's tendency to quickly forget played its role in the overall panicky attitude. Otherwise everyone would have noticed that there are no specific anomalies, but irregularly recurring phenomena. For example, in 1996 and 2003, heavy snowfall was observed in Moscow in early April.

Perhaps many have forgotten that similarly warm spring in Siberia was observed not that long ago, in 2012. As for the low temperatures in March, in 1888 and 1917 the average temperature this month in the central regions of Russia was -10.5C degrees. A record minimum temperature was observed in March of 1913 when for a few days the temperature did not rise above -32. 4C degrees. In March of this year the average temperature was -3.8C degrees.

it is obvious that talks about anomalies are not quite justified. It should be remembered that Russia is a northern country, located near the Arctic. It often presents such surprises, regardless of the time of year. The current non-standard weather is most likely also its handiwork. More precisely, it is caused by a stratospheric circumpolar cyclone, which, as its name implies, is raging in the upper atmosphere directly above the pole.

Although the first such natural phenomenon was recorded in 1952, scientists still do not know much about it. It is believed to be formed and developed to the extent that the atmosphere loses heat to space during the long polar night at altitudes of 30 to 50 kilometers. Although it is quite high, this cyclone may affect the movement of air masses in the lower levels of our air envelope and change the movement on a whim.

At the beginning of this century, it was observed that the phenomenon of sudden stratospheric warming (a significant and sudden increase in temperature in the polar and sub-polar stratosphere in winter - sometimes up to 50 ° or more, which lasts about 10 days), can split this cyclone into two parts. On average, this happens about once every two years, and 2013 is one of them. It is difficult to say what causes the warming, but scientists have been regularly recording them since 1988 and can say for sure that it is a recurrent and quite normal phenomenon. Most often this warming occurs in February, but sometimes it happens in December and January.

Now, according to the National Oceanic and Atmospheric Administration of the United States (NOAA), the sudden stratospheric warming of this year was the worst in a decade. Perhaps this was due to the positive temperature anomalies on the surface of the oceans and active phases of the solar cycle, as this year the sun is very active. In addition, there were significant positive temperature anomalies in the north Indian Ocean and the northwest Pacific Ocean. As a result, as expected, the stratospheric cyclone was split into two parts that started pushing away from each other and shifted from the poles to the mainland.

And then, as suggested by specialists from the Russian meteorological service, one of them approached Eurasia and "pulled" cold air from the Arctic. However, spring has already begun, and warm air masses from the North Atlantic moved towards Russia (the same air masses provided for the warm end of February). However, a sudden whirlwind of Arctic air pushed them east, and brought over a cold air mass that covered all European Russia with snow (Ukraine was not spared either). The staggering stratospheric cyclone "canceled" the beginning of spring and extended winter in these regions by another month.


As a result, only Lower Volga and the region near the Caucasus did not suffer as they were not reached by the icy breath of the pole. The expelled warm air, following the usual for Eurasia path of west-east transfer, found itself in the southern regions of Siberia. Against all logic, spring came there earlier than in central Russia. As you can see, there is no global breakdown, but a quite normal phenomenon. Without any doubt, it is of local nature.

What should we expect next? In fact, according to meteorologists, all the worst is behind us, because at the end of March the cyclone retreated back to the pole. It only has a short time to live - until the end of April, as the upcoming north heat will cease its existence until next winter.
Anton Evseev