Climatologists at the German Alfred Wegener Institute have found a connection with permafrost thawing and increased numbers of beavers in Alaska and elsewhere in the Arctic. The scientists published their findings in the scientific journal Environmental Research Letters.
Initially, they investigated how Alaska’s reservoirs change due to permafrost melting, but in the course of their work they learned that beavers play an unexpected role in these global climate processes.
Analyzing satellite imagery of the western Alaskan city of Kotsebu over the past 20 years, climatologists have noticed that there are many more lakes and other small reservoirs. As a result their total area has increased by 8.3%.
Researchers have found that half of them have built beavers. It turns out that these animals find the potholes of old lakes, which dried up before the ice age, and build dams in them. As a result, these ponds are being re-filled with water. Over the past two decades, the number of such dams has grown exponentially.
“Beavers have begun to spread across the Arctic in recent decades, both because of global warming and because they are not currently hunted much,” said climate scientist Ingmar Nitze of the Alfred Wegener Institute.
According to him, as a result, not only have 56 new lakes appeared, but also the melting of permafrost, which is located under the bottom of the former dry hollows, because now thanks to beavers they are filled with warm water. As scientists assume, similar processes take place not only in Alaska, but also in Canada, and in the Eurasian regions with deposits of permafrost.
All this, according to the authors of the study, can significantly accelerate the melting of permafrost and trigger a chain reaction, due to which it will quickly disappear in the near future. This should be taken into account when predicting the future of the Arctic and how its shape will change in the coming decades, the scientists concluded.
On June 28, Swedish climate scientist Johan Kilensherna said that warming the climate in Siberia will lead to melting permafrost, which could destroy cities and villages in the region.