Permafrost Paranoia
The April issue of Nature highlights our lack of knowledge on how global warming will affect the permafrost. It’s an interesting question because if just 1% of the possible 1,800 Gt of organic carbon in the permafrost rotted and decomposed in a warmer world it would be as if we quadrupled our current rate of carbon emissions. (See the Nature article here.) There’s a lot we don’t know, but what we do know doesn’t suggest a crisis, especially in light of potential natural or man-induced adaptation.
Examination of carbon-14 levels indicates nature laid down the organic material in the permafrost a long time ago. About half the organic material sits deep enough that its decomposition produces methane and the methane levels emerging from this layer increased during the warming in the 1970s, but have been declining since then, despite increasing temperatures and melting. Several natural adaptations, including increased ground cover and tree growth also limit CO2 emissions. Alternatively, more and more organic matter becomes available for decomposition as temperatures rise, despite increased sequestration in plants. Modelers admit they don’t have a handle on the dynamics of this vast ecosystem yet and can’t say whether it’s appropriate to worry about a massive CO2 release from the permafrost, or loss of soils, etc. What is clear is that this new soil is ideal for many useful short-season crops, and aerial seeding of switch grasses, and the like might produce soil stability, massive carbon entrainment, and for the hardy, an economic crop.
In any case, the forest is advancing northward. Deer, elk and caribou herds are gaining pasturage. Bear are gaining habitat too. And someday, perhaps in the next few decades, those who wish a quiet and unique view of the northern lights may be able to find new hotels serviced by ship in places where before there was nothing but permafrost.