Forecasters predict that the anomalous heat in the European part of Russia will decrease on Tuesday, when will crumble unique anticyclone, demeanor here for almost two months - from June 21. This process, in their opinion, may be accompanied by hurricanes and tornadoes, which will fall to "well done" regions.
British scientists say they learned because of a natural phenomenon in Russia established an incredibly hot weather, but can not explain the mechanism of its occurrence.
Wait!
The first time since late June weather forecasterspromised a change in atmospheric circulation. The anomalous anticyclone not let the fresh air and rain in the center of Russia, replaced by the so-called zonal transport, told journalists on Thursday the director of Russia for Hydrometeorology Roman Vilfand.
Tuesday, 17 August, daytime temperatures should be lowered to 23-28 degrees Celsius, although this temperature for a fourth five-day week in August is much higher than normal.
Wind dispel smoke in Moscow and adjacent regions from the burning of peat bogs and forests.Downdraft typical anticyclone, will be replaced by rising, smoke and other combustion products begin to dissipate much quicker.
But this weekend could still be back in the capital - on Saturday and Sunday are expected calm weather with wind speed of about 1 meter per second.
However, according to the head Hydrometeorology, in 2010, smoke in Moscow less than during natural fires in 1972. According to him, while Moscow was zadymlena almost continuously from 21 July until the end of August.
Out of the fire - a "shower"
The destruction of the anomalous anticyclone may lead to such hazards as hurricanes and tornadoes. As a rule, the catastrophic phenomena observed during severe weather changes, they could provoke a strong horizontal movement of air, the head of Hydrometeorology.
However, in advance to predict such disastersforecasters have not yet learned. They can only assess the probability of such events.
Vilfand gave the example of American meteorologists who believe their significant achievement prolongation of the tornado warning from 6 to 12 minutes.
Meteorologists shocked
Scientists still can not understand what gave rise to large-scale environmental anomalies in Russiathis summer.
There are various methods by which you can get weather data from previous years - in particular, through the analysis of lake sediments. Chapter Roshydromet Alexander Frolov said that his department has "archive" of dangerous weather situations for a thousand years. And all this time anything like this in Russia is not happening.
"Catastrophic" called meteorological situation in the country director of the hydrometeorological center. According to him, the likelihood that in Central Russia in the summer the temperature will reach 36-40 degrees is so small that it can happen again in about 5000 years.
No meteorologist in past years would not have believed that the temperature in Russia could exceed the climatic norm by 7-8 degrees, according Vilfand. In his view, what is happening now is beyond the possible.
Russia summed up the jet stream?
Extreme heat in Russia and the disastrous floods in Pakistan have a common cause - to change the behavior of the so-called jet at high altitude in the atmosphere, said earlier meteorologist Mike Blackburn (Mike Blackburn) from the British University of Reading.
High-altitude jet stream (jet stream) - meandering streams of very strong winds, which are at altitudes from 7 to 16 kilometers. Currents running from west to east, may vary from north to south, forming the so-called wave Rosby (Rossby wave), resembling a river meanders or petals.
In recent weeks, meteorologists have noticed unusual changes in behavior of the jet stream. Typically, wave at them shifted to the east, "raking" a weather situations in general. However, in mid-July, these waves are "stalled," said Blackburn, quoted by the publication New Scientist.
Such steady education in the jet streams are called "blocking events, they occur when strong waves Rosby begin to move west against the flow. Usually within overpowers, but this time the "meander" remained in place, thus creating excellent conditions for extreme weather events, the scientist said.
In Pakistan, this situation coincides with the summer monsoon, which is due to "a frozen wave" in the jet stream brings more rain to the north of the country, which led to flooding. On the other hand, the loop current, long stay above Russia, provided a steady stream of hot dry air from Africa and the extreme heat.
Similar events somewhat earlier, in June, took place in the U.S..
Meteorologists can not yet say what makes "frozen" wave on the jet stream. Theory suggests that extreme weather events become more frequent as the climate warms, but the link between warming and the behavior of jets scientists is not yet clear.
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