Researchers from the Finnish Meteorological Institute have reliably estimated the amount of snow in the Northern Hemisphere.
They found that snow mass between 1980 and 2018 has remained the same in Eurasia and decreased in North America, but the extent of cover has decreased.
The changes were monitored using satellite observations and ground measurements.
Previous estimates varied so much that it was not possible to gain a coherent or reliable picture, but the Finnish researchers have developed a method reducing error margins.
Jouni Pulliainen, lead author of the paper and research professor at the Finnish Meteorological Institute, said, “The method can be used to combine different observations and it provides more accurate information about the amount of snow than ever before. The previous considerable uncertainty of 33% in the amount of snow has decreased to 7.4%.”
The researchers found little reduction in snow mass over the 40 years in the northern hemisphere at the annual maximum as February turns to March.
Snow cover decreases significantly especially in late spring, and the change is visible on the entire northern hemisphere and in the Arctic.
In northern areas where rainfall turns to snow, the mass remained the same or increased, but decreased in the south where winter rainfall comes down as water rather than snow.
This winter has had a much lower snow cover, especially in Europe, but the northernmost parts of Europe and Eurasia have had significantly more snow than average.
North America has had much more snow in northern latitudes with numerous snowstorms in early winter.