MOSCOW — Russia’s vast permafrost areas may shrink by a third by the middle of the century due to global warming, endangering infrastructure in the Arctic zone, an emergencies ministry official said Friday.
This AFP story snuck across my desk on little cat feet. It didn’t get much attention, in part because they buried the lede in the very last sentence:
Scientists have said that permafrost thawing will set off another problem because the process will release massive amounts of greenhouse gas methane currently trapped in the frozen soil.
Ya think?
The permafrost permamelt contains a staggering “1.5 trillion tons of frozen carbon, about twice as much carbon as contained in the atmosphere, much of which would be released as methane. Methane is 25 times as potent a heat-trapping gas as CO2 over a 100-year time horizon, but 72 (to 100) times as potent over 20 years!
The carbon is locked in a freezer in the part of the planet warming up the fastest (see “Tundra 4: Permafrost loss linked to Arctic sea ice loss“). Countless studies make clear that global warming will release vast quantities of GHGs into the atmosphere this decade. Yet, no climate model currently incorporates the amplifying feedback from methane released by a defrosting tundra.
Here’s more from the AFP story:
“In the next 25 to 30 years, the area of permafrost in Russia may shrink by 10-18%,” the head of the ministry’s disaster monitoring department Andrei Bolov told the RIA Novosti news agency.“By the middle of the century, it can shrink by 15-30%, and the boundary of the permafrost may shift to the north-east by 150-200 kilometres,” he said.The temperature of the zones of frozen soil in oil and gas-rich western Siberia territories will rise by up to 2 °C to just three or four degrees below zero, he predicted.Permafrost, or soil that is permanently frozen, covers about 63% of Russia, but has been greatly affected by climate change in recent decades.
Here is a good 2010 video on what is happening to the Russian tundra.
Back in the February, NOAA and the National Snow and Ice Data Center (NSIDC) dropped their own bombshell — Thawing permafrost feedback will turn Arctic from carbon sink to source in the 2020s, releasing 100 billion tons of carbon by 2100:
Figure: Carbon emission (in billions of tons of carbon a year) from thawing permafrost.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…. [Our] estimate may be low because it does not account for amplified surface warming due to the PCF itself…. We predict that the PCF will change the arctic from a carbon sink to a source after the mid-2020s and is strong enough to cancel 42-88% of the total global land sink. 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/NOAA study itself doesn’t even incorporate the CO2 released by the permafrost carbon feedback into its warming model! Even so, in their study, the permafrost is adding more than one billion tons of carbon a year to the atmosphere by the mid-2030s!
The authors note that of the dozen or so studies done to date on permafrost melt by 2100, “Our projections of permafrost degradation fall on the low side, but well within the range of other published projections.” An earlier NCAR-led study found half the land-based permafrost would vanish by mid-century on our current emissions path (see “Tundra, Part 2: The point of no return“).
This conservative study “found that between 29-59% of the permafrost will disappear by 2200.” Given that the head of the Russian ministry’s disaster monitoring department believes that 2 °C warming is enough to shrink up to 30% of the Russian permafrost by 2050 — and given that northern Russia is looking at as much as 10 °C warming by century’s end (see here) — I’d say we need to do a complete re-evaluation of the risk of losing most of the permafrost by century’s end, resulting in rates of carbon flux this century more than double what NSIDC/NOAA considered
Further, the NSIDC-led study acknowledges that it almost certainly underestimates the warming the PCF will cause. It assumes all of the carbon released will come out as CO2, not methane.If even half of the carbon comes out as methane, then the warming impact over a 20-year time frame would be 10 times as much!
Finally, that study only looked at the land-based permafrost. Let’s remember the study from last year:
Science: Vast East Siberian Arctic Shelf methane stores destabilizing and venting: NSF issues world a wake-up call: “Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.”Methane and carbon release from the Arctic is the most dangerous amplifying feedback in the entire carbon cycle. This research finds a key “lid” on “the large sub-sea permafrost carbon reservoir” near Eastern Siberia “is clearly perforated, and sedimentary CH4 [methane] is escaping to the atmosphere.”
Again, the “climate pragmatists” out there who think R&D or an energy quest is going to stop us from multiple catastrophes are deluding themselves and others. We need to start aggressive mitigation now as every major independent study concludes. And if we don’t, then those who follow the science at least have the moral obligation to warn the public about what is coming, so they can prepare, even if their political leaders refuse to do so (see “The GOP War Against Climate Adaptation“).
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