In Batagaika, in northern Siberia, we find the largest crater in the world. Caused by thawing permafrost, the land here has normally been frozen in all seasons for thousands of years. As it melts, permafrost releases treasures, like a mammoth bone. This phenomenon began in the 1960s. With global warming, the crater is widening by more than ten meters per year. Permafrost covers a quarter of the northern hemisphere. Almost all of the Russian region of Yakutia, where winter regularly reaches -40 degrees. Its melting causes damage: the ground subsides and draws circles which replace pastures.
What is permafrost? Nicolas Chateauneuf is on the 20 Hours set. “Permafrost covers vast areas of northern Canada, Russia and Alaska”, explains the journalist, using augmented reality. Most often there is tundra, with short grass. “Below, we find permafrost, the further down we go, the more the ground remains permanently frozen, sometimes with real pieces of ice encrusted.” The thickness can vary from a few meters to several kilometers. “With the warming, this layer thaws in depth […] as it thawed, the permafrost released bacteria. “ The risk is to release a virus hundreds of thousands of years old against which humanity would not be immune.