In early February 2012, much of Europe shivered under the effects of a “Russian Winter” - intense cold and snow triggered by a strong Siberian anticyclone which hovered over northern Russia. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured this true-color image of the snowy landscape of France and the United Kingdom on February 11, 2012.
In the coldest parts of the year, when the intense cooling of the surface layers of air over northeastern Siberia occurs, the time is right for the formation of a Siberian anticyclone. Also called a Siberian high, it is a semi-permanent system of high atmospheric pressure centered in northeastern Siberia. The Siberian anticyclone is one of the principal sources of polar air masses, and outbreaks of polar air westward from the high-pressure area can cause severe cold spells in the European continent.
In early February, 2012, a strong anticyclone formed over northern Russia. On February 3, Mosfiloti Weather Service reported a high pressure of 1061 hPa in that area. Set against a depression almost 70 hPa lower in southern Greenland, it was a driving force to push frigid temperatures across Europe. On February 10, CNN reported that twenty-two countries had posted warnings for extreme cold temperatures and accumulating snow. Temperatures of -17 °C (1.4 °F) were reported in Romarantin and -16 °C (3 °F) in Bergerac, France on February 7.
The cold has reached as far south as Algeria, bringing a rare snowfall. The bitter cold and snow not only has been inconvenient, tangling traffic and cutting off villages from essential services, especially in Eastern and Central Europe, but it has been deadly as well. On February 14, the Telegraph reported at least 306 deaths across the continent. The Ukraine has been the hardest hit, with over 131 cold-related deaths reported.