Over the past few posts, we've explored some of the negative impacts, both locally and globally of melting permafrost. This time round, I'm going to have a look to see if there might actually be some positives to come out of this process too.
Perhaps the most obvious example of a positive that can come out of this is how thawed out land, that was once covered in permafrost can often provide incredibly fertile land for agriculture. The rich organic soils that accumulated over 1000's of years provide an incredibly nutrient rich base for the planting of crops, especially vegetables such as potatoes and cabbages (which are naturally cold resistant). However, there is a serious drawback to 'reclaiming' thawed out permafrost areas. These areas often exhibit thermokarst (mounds and hollows in the landscape where the frozen earth meted at different rates) which evidently reduce the capacity for large scale arable farming due to the unevenness and irregularity of the soil surface. This can be countered by grading (levelling out) the landscape, but this process is both expensive, and labour intensive which decreases any potential benefits (Contributions to Alaskan Geology).
A second potential benefit could be the harvesting of the previously mentioned methane clathrate, as according to the USGS, there is an estimated 700 000 trillion cubic feet of this substance (also known as methane hydrate) around the world, much of which is currently locked away under permafrost. This energy source has more potential energy than all discovered oil and gas reserves combined (Wall Street Journal). It must be noted that not all of these estimated reserves are found under permafrost, though the vast majority is/was formed under permafrost conditions. This is then combined with the extra ease of access to existing oil and gas reserves, as the costs of both extraction and transportation involved are much lower when the soil is unfrozen, as drilling and pipeline construction is easier.
Hydrocarbons are not the only natural resource that becomes easier to access with retreating and thinning permafrost - minerals are follow the same line. Sites upon which profits would have been marginal due to high extraction costs from the frozen soil become more economically viable once such soil thaws, as again, drilling and mining is easier in the softer soil horizons (Brown, 1970). One such example of this is the iron ore deposits in Labrador, Canada. Operations only became viable after the permafrost had thawed to such a depth that the previous increased costs of extraction were minimised to economically viable depths (Seguin, 1974).
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