Climate change: Impact of thawing permafrost assessed

 
A paper suggesting that about 30-50% of critical Arctic peripheral infrastructure may be at high risk of being damaged as a result of permafrost thawing due to anthropogenic warming, Nature Reviews Earth & Environment Will be posted.The journal is a collection of papers investigating the physical changes, biogeochemical changes, ecosystem changes and their associated effects associated with the thawing of permanent frozen soil, and describes the findings obtained from this study. Is one of them.

The permafrost region of the Arctic stores approximately 1 trillion tonnes of frozen and thawed carbon.Some of these carbons can be released into the atmosphere by anthropogenic warming and affect the climate in multiple processes collectively referred to as "permafrost carbon feedback."The melting of permafrost poses a major threat to the integrity of polar and high-altitude infrastructure.

Now, Jan Hjort and colleagues say that under conditions of anthropogenic warming, about 69% of permafrost housing, transportation and industrial infrastructure may experience permafrost near the surface by the mid-21st century. It reports that it is located in a high-quality area.As a result, infrastructure costs associated with permafrost degradation could amount to tens of billions of dollars by the second half of the 21st century.For example, in Russia, the total cost of supporting and maintaining road infrastructure due to the deterioration of permafrost from 2020 to 2050 is 4220 billion rubles (about 6330 billion rubles) on the existing road network, without additional road construction. It is estimated to reach XNUMX billion yen). Hjort et al. Point out that there are a certain number of techniques to mitigate these effects, one example of which is air convection embankment (using a porous rock layer to generate convection in the embankment to remove heat). Improves sex), but concludes that a better understanding of high-risk areas is needed for effective mitigation methods.

In the review by Sharon Smith et al. Included in this collection of papers, there are spatial fluctuations in permafrost temperature rise due to the interaction of climate, vegetation, snow cover, organic layer thickness and ground ice content. It has been pointed out.In the warm permafrost found in the sub-Arctic region (temperatures close to 0 ° C), the warming rate is generally less than 10 ° C per decade.In contrast, cold permafrost (temperatures below -0.3 ° C) found in the high-latitude Arctic clearly shows that temperatures rise to about 2 ° C per decade. Smith et al. Conclude that a deeper understanding of the longer-term interaction of permafrost with the surrounding environment is needed to reduce uncertainty about the thermal state of permafrost and its future response. ing.

Each article in this collection outlines not only how permafrost and the role of permafrost in the Earth's system have progressed, but also the vast amount of uncertainties and unexplained points. Has been done.Cooperation is the key to predicting and mitigating the effects of permafrost melting.

 
* This article is reprinted from "Nature Japan Featured Highlights".
Reprinted from: "Climate change: assessing the impact of permafrost thawing'