In late February, scientists summed up the results of the winter calendar. She broke several temperature records, becoming the most warm not only in individual regions, but throughout the Northern hemisphere and the whole planet over the entire history of observations since 1880. About it writes BBC.
This particularly warm winter was in Russia.
If the whole Europe from December to February was warmer by about 3°C compared to the average figure for the years 1910-2000, in Moscow, St. Petersburg and even Novosibirsk weather ahead mean monthly temperature at seven degrees even compared to relatively recent years 1981-2010.
For comparison: in London this winter are above the average temperature was slightly less than 2°C, in new York city and Vladivostok is about 3°C in Montreal — almost 4°C.
A month ago, the Russian hydrometeorological centre warned: “the Temperature requirements Jan deflected at 4-12 degrees Celsius or more. In the Central Federal district the average temperature of January 2020 reached an absolute maximum”.
In February weather anomaly not only not improved, but also deviated from the norm even more. In the Russian capital even set a new absolute record heat of winter: on 19 February, the thermometer rose to +4,7°C.
What is the reason?
In spite of the obvious obvious explanation, it is not global warming — at least certainly not directly.
The average temperature on the planet actually grow, but not so fast. Over the past 20 years the planet warmed about 1.14°C — compared to the average figures of the last century.
The main cause of the current weather anomalies — not only in Russia but also in Europe and in the USA in the other.
Usually cold weather in the Northern hemisphere brings cold air from the Arctic, breaking in low latitudes, together with cyclones and anticyclones. However, in December, 2019 in the region of the poles formed an extensive area of low pressure which locked the cold in the North, not allowing Arctic air masses to break through to the South.
In January 2020, this state of Affairs was established, and eventually almost the whole winter winds walking in a circle in the far North of the planet, almost reaching the inhabited areas of the continent.
“This card is well observed circumpolar motion, that is, General movement around the pole, preventing the breakouts of cold,” explains associate Professor in the Department of meteorology and climatology SGU Svetlana Morozova.
“Very often cold winter in the European part of Russia explain the influence of the Western periphery of the Asian winter anticyclone. But it forms a highly cold weather only when its replenishment of the Arctic air, that is, the same breakthroughs,” adds her colleague Seraphim Lapin.
In the absence of additional supply of cold portions of air from the Arctic winters are usually quite warm, meteorologists explain. Just this year, the zonal circulation was incredibly stable and lasted almost the entire season.
Why this happened and has this ever happened before?
The possible reasons are so many that no one person is a meteorologist will not undertake anything for sure — at least for now. According to head of the Department of meteorology and climatology TSU Valentina Gorbatenko, will have to wait at least a year when the cycle will end and it will be possible to perform.
But in General, deviations from a multiyear average, even such strong is fine, says the Professor. They should not be considered as something totally unprecedented and panic due to the excessively warm winter.
In 2019, for example, the situation was exactly the reverse. January was abnormally cold because of the breakup of the polar vortex, one edge of which is claimed in the Eastern part of Siberia and the other in the United States. The cold was such that several States have declared a state of emergency.
And the reasons can be mass, because the earth’s atmosphere — “it’s such a big pan where it is boiled weather, and there are so many factors that all of them into account is simply impossible”.
“Say, melting ice in the Arctic changing the salinity, density, circulation. And as a result there are some microcirculation violations — not only in the atmosphere but in the ocean, and not all of them are visible. That is, the redistribution of long-term, centuries-old centers of action of atmosphere,” explains Professor Gorbatenko.
To predict such changes, she said, is also impossible — how and make conclusions about what will be the rest of the year: the same warm, or conversely, colder than usual.
Any predictions are generally always constructed in retrospect: in the past searched for counterparts of similar situation, and the basis for their conclusions. Such a sequence of processes, as this year, scientists have never recorded. So, even if we place all the known and unknown data in the most powerful computer, unlike anything he can find.
But this, according to the Professor, it means nothing.
“Yes, in the history of instrumental observations and our memory that never happened. But this tells only that this has not happened in approximately the last 140 years. It was, like, 160 years ago, we do not know. But the climate cycles of tens of thousands of years,” she recalls.
“Human life is too short and each of us has in memory some special years that we remember, “Oh, I never such weather is not seen!” But that means nothing. Maybe that happens after 60 or 100 years — maybe next year. But it is exactly the same will not mean anything,” — concludes the Professor.