Photo: Rebecca Neumann / University of Washington
Scientists at the University of Washington (USA) came to the conclusion that the early spring rains enhance erosion of permafrost (permafrost zone), which is including in Siberia, and contribute to releasing large quantities of methane — a greenhouse gas, amplifying global warming. About it reported in a press release on Phys.org.
Researchers have studied the processes of melting of the permafrost in the frozen marshes of the permafrost zone, located approximately 32 kilometers from the city of Fairbanks (AK), from 2014 to 2016. Specialists monitor the emissions of methane in swamps and around them, the growth of sedge and modify the soil temperature at 16 different depths.
In 2016, the scientists noticed that the temperature of the soil at the edge of the permafrost zone increased by 20 days earlier than usual, and the total methane emissions increased by 30 percent compared to previous years. The amount of precipitation was above average, as in 2014. The main difference 2016 from 2014 was that the spring rains started earlier. Since early spring the air is warmer lands, precipitation heat the soil. The soil quickly becomes saturated with moisture, the excess of which flows into the frozen swamps and raises their temperature.
Warm, swampy soil, in turn, accelerates the metabolism of microbes that because of the lack of oxygen begin to oxidize available organic matter, releasing methane. Heating of the soil is confirmed by the fact that around the marshes began to grow more sedges. These plants also provide organic matter to the microorganisms and facilitate the release of methane through the stems.
With the increase in the average temperature of the Earth due to anthropogenic emissions of spring precipitation in Northern latitudes will fall all the sooner. Wherever there is permafrost, including Siberia, will increase the rate of thawing of frozen soils and the volume of methane that is released. Furthermore, the destruction of the permafrost zone can lead to the destruction of built infrastructure and buildings.
Video, photo All from Russia.