The winter of 2010 was unusually cold and snowy for most of Europe. On most days between mid-December and mid-March, the mean temperature was below normal across much of the continent. Below are E-OBS mean temperature anomalies for December through February.
E-OBS anomalies for mean temperature for December 2009 through February 2010 compared to the normal period 1961-1990.
The anomalously cold temperatures contributed to significantly more ice days, where the maximum temperature is below freezing, than normal. Most areas saw between 10 and 20 additional ice days from December through February, but some areas in Southern Scandinavia had over 30 more than normal. See the ECA&D anomaly map below.
ECA&D anomaly map of the number of ice days, where the maximum temperature is below 0°C, for December 2009 through February 2010 when compared to the normal period 1961-1990. Please click on the map for its most recent version.
One of the coldest days was 19 December. This day was extremely cold across most of Europe with large areas experiencing minimum temperatures below -20°C, including -44°C at the Northwestern Russian Federation station Ust Tzilma, -34°C at Drevsjo in Norway, and -27°C on the Zugspitze summit in Germany. See the ECA&D station map below.
ECA&D station map of minimum temperature across Europe on 19 December 2009.
Though this particular winter in Europe was colder than average and had more ice days than normal, there has been a clear trend toward a decrease in the number of ice days during winter on the order of 3 days per decade during the period 1961-2010 (see the ECA&D trend map below). This is consistent with the strong trend toward winter warming by an average of 1 to 1.5°C per decade over the past 50 years.
ECA&D trend map of the number of ice days during winter (December, January and February) for the period 1961-2010. Please click on the map for its most recent version.
The winter of 2010 was also abnormally snowy across Europe due to a succession of snow storms that caused heavy snow to fall from Spain to Ukraine throughout the period. Due to the prolonged cold temperatures and the frequency of snow storms, the number of days with greater than, or equal to, 1 cm of snow on the ground was significantly greater than normal across Europe. Some locations in Norway had between 40 and 60 more snow days than normal and most of Northern Germany had from 20 to 40 more snow days. In the Netherlands, there were on average 41 days with snow, the highest since 1979 and 28 days above the 1961-1990 normal. See the ECA&D anomaly map of the number of snow days below. Note that snow data is currently not available for all countries since ECA&D only recently started gathering data for snow.
ECA&D anomaly map of the number of snow days, where greater than or equal to 1 cm of snow is on the ground, compared to the 1961-1990 normal. Please click on the map for its most recent version.
Though the winter of 2010 had anomalously more snow days than normal, the long-term trend according to ECA&D data from 1961-2010 is toward a significant decrease in the number of snow days on the order of 8 to 12 below normal.
The National Oceanic and Atmospheric Administration (NOAA) reports that, just as Northern Europe (and the eastern half of the United States) was experiencing abnormally cold conditions for winter, areas of North Africa, Northeastern Canada and Greenland were experiencing anomalously warm weather, at nearly 8°C above normal. Such a distribution of warm and cool air over the planet is due to the air pressure being much higher than normal in the polar regions and lower than normal in the subtropical Atlantic and Pacific oceans. This resulted in an extremely strong, negative Arctic Oscillation (AO); the highest measured since the beginning of observations in 1900. Though there were clear areas of warm and cool, the net result over the entire globe was the second warmest December-February on record.