Beneath much of the Arctic resides vast stores of greenhouse gases, locked up for millennia in icy soils. With this in intellect, a pair of studies offer a double whammy of bad news: Not merely are these frozen reservoirs thawing out more extensively than previously known, but at this stage, theres little that can be done about it.
Carbon dioxide and methane are indubitably the two most potent greenhouse gases. Vast reservoirs of both exist within the worlds permafrost, which is hydrated clay that has remained below the freezing point for two or more years. Remarkably, these permafrost soilshold almost twice as much carbon than that found in the atmosphere and one analyze, published in Nature Geoscience, shows them thawing all across the northern hemisphere.
Thanks to consistently warmersummers, permafrost in Russia, Alaska and Canada is being uncapped; icy wedges that kind at the top of the permafrost were observed to be almost universally melting even in the coldest regions of the Arctic. These wedges make up around 20 percentage of the upper permafrost volume, so their melting is exposing massive areas of concealed, deeper permafrost.
The scientific community has had the assumption that this cold permafrost would be protected from climate warming, but were showing here that the top of the permafrost, even if its very cold, is very sensitive to these warming events, Anna Liljedahl, the lead writer of such studies and a researcher at the University of Alaska in Fairbanks, told the Washington Post.
Permafrost is melting in even the coldest regions, and by 2100, massive amounts of greenhouse gases will be released skywards. Liljedahl et al ./ Nature Geoscience
Importantly, permafrost isnt the only icy prison for greenhouse gases. Around56 million years ago, there was a mysterious, sizeable, global spike in atmospheric carbon. One of the prevailing theories is that this took place when a huge cache of frozen methane beneath the seabed was abruptly destabilized, causing it to release its contents into the atmosphere as both methane gas and carbon dioxide. This, in turn, caused dramatic global warming, and a similar turn of events could happen today if the permafrost stores are unleashed.
It might even getting worse: The initial uptick in global temperatures could further destabilize both reservoirs of frozen greenhouse gases, which in turn would release more trapped gas, and so on. Once this cycle reaches a certain tipping point, it may be impossibletoprevent.
So is there any style to avoid this, aside from agreeing to cut greenhouse gas emissions on a world scale? Some have suggested that plants, which would begin to proliferate in a warmer Arctic, could end up soaking up the escaping carbon dioxide, acting as a biological buffer to this increasingly troubling phenomenon.
Another study was commissioned to ask 100 Arctic researchers if this was plausible, and they gave a resounding answer: no, its not. The research, published in Environmental Research Letters, concluded that the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario.
This means that, whatever happens, a vast chunk of its carbon will inexorably escape to the atmosphere by the end of the century. However, they do point out that up to 85 percent of permafrost carbon release could be stopped if human emissions are actively reduced.