The sudden melting of a bog the size of France and Germany combined could unleash billions of tonnes of methane, a potent greenhouse gas, into the atmosphere.
The news of the dramatic transformation of one of the world’s least visited landscapes comes from Sergei Kirpotin, a botanist at Tomsk State University, Russia, and Judith Marquand at the University of Oxford.
Kirpotin describes an “ecological landslide that is probably irreversible and is undoubtedly connected to climatic warming”.He says that the entire western Siberian sub-Arctic region has begun to melt, and this “has all happened in the last three or four years”.
What was until recently a featureless expanse of frozen peat is turning into a watery landscape of lakes, some more than a kilometre across.Kirpotin suspects that some unknown critical threshold has been crossed, triggering the melting.
Western Siberia has warmed faster than almost anywhere else on the planet, with an increase in average temperatures of some 3 °C in the last 40 years. The warming is believed to be a combination of man-made climate change, a cyclical change in atmospheric circulation known as the Arctic oscillation, plus feedbacks caused by melting ice, which exposes bare ground and ocean. These absorb more solar heat than white ice and snow.
Source: Fred Pearce, NewScientist.com