08-01-2017, 02:57 AM
Quote:In northern Siberia, rising temperatures are causing mysterious giant craters — and even more dire consequences could be in store, say climate scientists. The Russian province's long-frozen ground, called permafrost, is thawing, triggering massive changes to the region's landscape and ecology. It could even threaten human lives. "The last time we saw a permafrost melting was 130,000 years ago. It's a natural phenomenon because of changes in the earth's orbit," said professor of earth sciences at the University of Oxford, Dr. Gideon Henderson.Siberian craters: Big releases of methane could pose broad problems
"But what is definitely unprecedented is the rate of warming. The warming that happened 130,000 years ago happened over thousands of years … What we see happening now is warming over decades or a century." We are therefore seeing a much more rapid collapse of the permafrost, Henderson said.
It's clear that the thawing permafrost has an important effect on the climate, Henderson said. Under normal conditions, permafrosts regulate the amount of carbon in the environment by taking up and storing significant portions of carbon that humans release from burning fossil fuel.
In the case of Siberia, this equation is being reversed. "When [permafrosts] release carbon, it will accelerate the rate of warming in the future," Henderson said. A self-reinforcing feedback loop is created whereby warming releases more carbon, which in turn produces greater warming.