Paris: Climate change could release unexpectedly huge stores of carbon dioxide from Arctic soils, which would in turn fuel a vicious circle of global warming, a new study warned on Sunday.

And according to one commentary, current models of climate change have not taken this extra source of greenhouse gas into account. Scientists have long known that organic carbon trapped inside a blanket of frozen permafrost covering one fifth of the world's land mass would, if thawed, release greenhouse gases into the atmosphere.