Far Northern Permafrost May Unleash Carbon Within Decades (JPL/NASA)

March 5, 2018

Permafrost in the coldest northern Arctic -- formerly thought to be at least temporarily shielded from global warming by its extreme environment -- will thaw enough to become a permanent source of carbon to the atmosphere in this century, with the peak transition occurring in 40 to 60 years, according to a new NASA-led study.

The study calculated that as thawing continues, total carbon emissions from this region over the next 300 years or so will be 10 times as much as all human-produced fossil fuel emissions in the single year 2016.

The study, led by scientist Nicholas Parazoo of NASA's Jet Propulsion Laboratory in Pasadena, California, found that warmer, more southerly permafrost regions will not become a carbon source until the end of the 22nd century, even though they are thawing now. That is because other changing Arctic processes will counter the effect of thawing soil in these regions.

The finding that the colder region would transition sooner than the warmer one came as a surprise, according to Parazoo. "Permafrost in southern Alaska and southern Siberia is already thawing, so it's obviously more vulnerable," he said. "Some of the very cold, stable permafrost in the highest latitudes in Alaska and Siberia appeared to be sheltered from extreme climate change, and we didn’t expect much impact over the next couple hundred years."
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more: https://www.nasa.gov/feature/jpl/far-northern-permafrost-may-unleash-carbon-within-decades
full paper: https://www.the-cryosphere.net/12/123/2018/