If permafrost is increasingly thawing in Siberia, the consequences could be felt worldwide. Because more greenhouse gases are released. How much does this affect the climate?
Moscow (dpa) - If climate change has a greater impact in Siberia, not only Russia will be affected. In large areas, the ground is frozen to great depths all year round.
With rising temperatures, it thaws faster and faster - it is one of the most visible consequences of global warming. "At the moment, we are primarily observing a very rapid course of certain dew processes," says Mathias Ulrich, geographer at the University of Leipzig. That could affect the global climate - and the people in Siberia.
You only felt the forces of nature on your own doorstep last year. The taiga, which is important for the global climate, burned for months. There were severe floods just a few hours' drive from Lake Baikal. Kremlin chief Vladimir Putin addressed his compatriots shortly before Christmas: "We have to do everything we can to stop climate change."
Almost two thirds of the floor area in Russia is permanently frozen. The phenomenon is called permafrost. This huge freezer contains immense amounts of remains from plants and animals that have not yet been decomposed by microbes. These only become active when the temperatures rise and the soil softens.
Such ancient permafrost can be found especially in Alaska, Canada and in the east and north of Siberia - from the Arctic Ocean to part of the Urals and in the south to Kazakhstan. The frost can reach a depth of one kilometer or more. However, as the arctic winters get warmer and the summers are longer, the layers of earth are thawing ever deeper. According to the World Weather Organization (WMO), 2019 was the second warmest year since weather records started in 1880. And even in the years before, there were always new temperature records.
"Today we know that large amounts of carbon are bound in the permanently frozen soil, probably about twice as much as is currently present in the atmosphere," says permafrost expert Ulrich. If the soil thaws over a large area, this store will open. "There would be enormous greenhouse gas emissions, which in turn would exacerbate current global warming."
The ultimate impact depends on how much man-made carbon dioxide (CO2) and methane are released into the atmosphere. "In many respects, the existing permafrost models are currently slower in their response to warming than the reality of the observations shows us," says Guido Grosse of the Alfred Wegener Institute in Potsdam.
If large quantities of greenhouse gases are released, the goal of limiting global warming to an acceptable level would be even more difficult to achieve, the professor of permafrost research predicts. Precise predictions are also difficult because humans can control the emission of carbon dioxide in industry or transport. According to Grosse, a reduction would help "that the permafrost thaws less and that fewer additional emissions are to be expected there".
In view of the large areas of frozen ground, the output there, in turn, cannot be controlled, says Grosse. The UN environmental program Unep also warns of a possible domino effect. Scientists from the Russian University of Tomsk, together with their colleagues from other countries, did not determine until January that the average annual temperature in Siberia had increased by almost four degrees in the past 50 years.
Russia's freezer will continue to thaw. Jelena Parfjonowa from the Forest Institute of the Russian Academy of Sciences in Krasnoyarsk estimates that if the greenhouse gas emissions are not reduced, the permafrost area could shrink by 25 percent by 2080. So far it is 30 times the size of Germany.
Scientists at Oxford University recently demonstrated once again in a study that permafrost is sensitive. You see a connection between the melting of the Arctic ice and the softening of this soil. "Such a loss of sea ice is likely to accelerate the thawing of permafrost in Siberia," they explain in the journal "Nature". If the sea is free of ice, the scientists say, the air can absorb more moisture and bring snow to Siberia in autumn. As a result, extreme frost can no longer penetrate as deep into the ground.
Whole regions in Siberia could change if the ground thaws and sags or mountain slopes slide off. "With the defrosting of ice-rich permafrost, any infrastructure - buildings, roads, airstrips and pipelines - is damaged locally or is massively more expensive to maintain," says Grosse. The Kremlin also recently warned that global warming could threaten more natural disasters in some regions of Russia, such as the flood of the century last year.
There are also completely different consequences: The thawing soil always releases sensational finds. Mammoths, horse fossils, prehistoric puppies for example. In 2013, the remains of an extinct elephant with preserved muscle tissue and blood were found. Researchers who follow the traces of primeval life are enthusiastic. "This is good for us," says paleontologist Albert Protopopow from the Yakutia Academy of Sciences in northeastern Russia. "We're trying to find fossils quickly." Because thawed remains in the air decay quickly and are lost forever.
Alfred Wegener Institute on Permafrost
Permafrost studies at the University of Leipzig
University of Tomsk