如果我们只考虑的气候影响北极海岸侵蚀,还有双方的相关的问题是北极永久冻土的海岸侵蚀。第一面是目前有多大作为{有限公司}_2美元来源,第二是它拥有多少的风险为未来的气候变化。它的当前贡献的答案是,它不是很相关。根据“北极海岸动力学数据库:一个新的分类方案和统计在北极永久冻土海岸线][1]从2011年”,在汽车列车有101447公里的海岸线,和海岸侵蚀的速度是0.5米/年平均后滩高程为8.3米。乘以所有这些数字我们得到421005050 m ^ 3美元的北极土壤失去了每年向大海。这纸是收费,所以我在这里复制表2(最上面数字从何而来)和相关的图6。[!(在这里输入图像描述)[2]][2][![在这里输入图像描述][3]][3]表2还表明~ 2%重量的,失去了土壤对应的碳,所以使用体积密度1900 kg / m ^ 3美元([源][4])得到了对应于0.00002 Pg C每年(peta克碳),一个非常小的数量比~ [7.8 Pg C,燃烧化石燃料向大气中每年][5]。现在,更多的关于潜在的冻土丢失。 Scientist have studied Arctic ocean sediments and found that during the period of fast sea level rise at the end of the last ice age, a huge amount of organic carbon stored in permafrost were released ([source][6]), perhaps close to 1,000 Pg ([source][7]). Carbon that was then available for microorganism to metabolize and transform into greenhouse gases as carbon dioxide and methane. This greenhouse gases helped warming the Earth and melting the ice caps that covered it at that time. There are still about 1,300 Pg of carbon stored in permafrost ([source][7]). Thawing of permafrost is increasing rapidly. As well as coastal erosion rates. In coastal Alaska for example it have increased from 6.8 m/yr in 1955-1979, to 8.7 m/y in 1979-2002, to 13.6 m/yr on 2002-2007 ([source][8]). Arctic warming, sea level rise and release of permafrost organic carbon form part of a dangerous positive feedback cycle that we don't know how far or how fast it can go. And it have the potential to release massive, and this time, VERY considerable quantities of greenhouse gases into the atmosphere. [1]: https://link.springer.com/article/10.1007/s12237-010-9362-6 [2]: https://i.stack.imgur.com/YVkhm.png [3]: https://i.stack.imgur.com/MzzLT.jpg [4]: https://www.earth-syst-sci-data.net/10/355/2018/essd-10-355-2018.pdf [5]: https://www.researchgate.net/publication/311760100_Perspectives_on_the_Terrestrial_Organic_Matter_Transport_and_Burial_along_the_Land-Deep_Sea_Continuum_Caveats_in_Our_Understanding_of_Biogeochemical_Processes_and_Future_Needs/figures?lo=1 [6]: https://www.nature.com/articles/s41467-018-06080-w [7]: https://www.nature.com/articles/ncomms13653#ref1 [8]: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008GL036205
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