Experts of the Tomsk State University found a significant accumulation of greenhouse gases (carbon dioxide and methane) in Western Siberia's reservoirs in winter, and they vigorously break through to the surface during the spring ice retreat. The researchers supposed that winter is a period of gases accumulation, and the spring ice meltdown provokes a sharp release of carbon accumulated over the cold season. Under the ice, the concentration of carbon dioxide and methane used to increase by spring. According to the obtained data, in late winter, after the ice opening, carbon dioxide emissions may increase by 7-8 times, and methane emissions - by more than ten times. They are effective "valves" that regulate over a year emissions of carbon dioxide and methane into the atmosphere.