Friday 18 February 2011

Rethink! Melting permafrost rewrites the picture


The amount of carbon released is equivalent to half the amount of carbon that has been released into the atmosphere since the dawn of the industrial age. That is a lot of carbon.”


Every now and again research is published which changes our understanding so significantly that nothing less than a complete revision in thinking is required.

When that happens concerning climate change, nothing less than a complete revision of our responses to it is demanded too.

Such a research paper was published three days ago, one which rewrites the bleak prognosis for climate change yet more grimly.

The paper, entitled Amount and timing of permafrost carbon release in response to climate warming compels a complete revision of our assumptions concerning the continued human emissions of greenhouse gases.

That means of the fundamental assumptions which underlie the UNFCCC climate change negotiations internationally, and the actual and planned responses by government at all levels, globally.

The reductions so far envisaged, already inadequate to avert catastrophe, must now be revised down yet further and all responses, at every level, must follow suit.


The paper deals with the vexatious issue of the melting of permafrost – which we know very well is already happening because of its very visible effects, including those on the infrastructure.

The key finding is that a positive feedback, the permafrost carbon feedback (PCF) operates, by which the greenhouse gases released by the melting permafrost cause the temperature to rise, thus melting more permafrost, releasing more greenhouse gases, and so on.

The thaw and release of carbon currently frozen in permafrost will increase atmospheric CO2 concentrations and amplify surface warming to initiate a positive permafrost carbon feedback (PCF) on climate.’


The quantities of carbon involved are mind boggling. The paper states:

Although uncertain, the total amount of frozen permafrost carbon is on par with the amount of carbon currently in the atmosphere.’

In the NSIDC press release lead author Kevin Schaefer quantifies it like this:

The amount of carbon released is equivalent to half the amount of carbon that has been released into the atmosphere since the dawn of the industrial age. That is a lot of carbon.’


Other findings of key significance are that the permafrost carbon feedback is predicted to:

  • change the Arctic from a carbon sink to a source after the mid 2020’s

  • be strong enough to cancel 42-88% of the total global land sink.

  • and that once initiated, the PCF is irreversible and strong compared to other global sources and sinks of atmospheric CO2 , even with large uncertainties.’


The policy conclusions are irrefutable. The paper quietly understates them thus:

The thaw and decay of permafrost carbon is irreversible and accounting for the PCF will require larger reductions in fossil fuel emissions to reach a target atmospheric CO2 concentration.’

The NSIDC press release is a little more forthright:

They estimate an extra 190 plus or minus 64 gigatons of carbon will enter the atmosphere by 2200—about one-fifth the total amount of carbon currently in the atmosphere today. Carbon emissions from thawing permafrost will require greater reductions in fossil fuel emissions, to limit the atmospheric carbon dioxide to some maximum value associated with a target climate, Schaefer said. “It means the problem is getting more and more difficult all the time,” he said. “It is hard enough to reduce the emissions in any case, but now we saying that we have to reduce it even more.”

[nb the paper notes the 190 ± 64 gigatons estimate is probably low]

The source of this unwelcome news is impeccable: joint research between the National Snow and Ice Data Center and the National Oceanic & Atmospheric Administration, two organisations at the pinnacle of climate science with unimpeachable credentials.


Here are links to

a short report by Canadian Press published by the Toronto Star

the NSIDC press release

the paper in synopsis and full

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