Two thirds of permafrost likely to melt by 2200
Two-thirds of permafrost is likely to melt by 2200, thanks to global warming which will loft vast quantities of carbon into the air.
"The carbon resides in permanently frozen ground that is beginning to thaw at high latitudes, will impact not only the climate but also strategies to reduce fossil fuel emissions," said University of Colorado-Boulder's Kevin Schaefer, who led the study.
"If we want to hit carbon dioxide concentration, then we have to reduce fossil fuel emissions that much lower than previously thought to account for this additional carbon from the permafrost.
"Otherwise we will end up with a warmer Earth than we want," added Schaefer, the journal Tellus reports.
The escaping carbon comes from plant material, primarily roots trapped and frozen in soil during the last glacial period that ended roughly 12,000 years ago, he said, according to a Colorado statement.
Schaefer, research associate at Colorado's National Snow and Ice Data Centre, linked the mechanism to storing broccoli in a home freezer.
"As long as it stays frozen, it stays stable for many years," he said. "But if you take it out of the freezer, it will thaw out and decay".
While other studies have shown that carbon has begun to leak out of permafrost in Alaska and Siberia, the study by Schaefer and his colleagues is the first to make actual estimates of future carbon release from permafrost.
