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标题：Centuries of thermal sea-level rise due to anthropogenic emissions of short-lived greenhouse gases
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作者：Kirsten Zickfeld ; Susan Solomon ; Daniel M. Gilford 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2017
卷号：114
期号：4
页码：657-662
DOI：10.1073/pnas.1612066114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Mitigation of anthropogenic greenhouse gases with short lifetimes (order of a year to decades) can contribute to limiting warming, but less attention has been paid to their impacts on longer-term sea-level rise. We show that short-lived greenhouse gases contribute to sea-level rise through thermal expansion (TSLR) over much longer time scales than their atmospheric lifetimes. For example, at least half of the TSLR due to increases in methane is expected to remain present for more than 200 y, even if anthropogenic emissions cease altogether, despite the 10-y atmospheric lifetime of this gas. Chlorofluorocarbons and hydrochlorofluorocarbons have already been phased out under the Montreal Protocol due to concerns about ozone depletion and provide an illustration of how emission reductions avoid multiple centuries of future TSLR. We examine the “world avoided” by the Montreal Protocol by showing that if these gases had instead been eliminated in 2050, additional TSLR of up to about 14 cm would be expected in the 21st century, with continuing contributions lasting more than 500 y. Emissions of the hydrofluorocarbon substitutes in the next half-century would also contribute to centuries of future TSLR. Consideration of the time scales of reversibility of TSLR due to short-lived substances provides insights into physical processes: sea-level rise is often assumed to follow air temperature, but this assumption holds only for TSLR when temperatures are increasing. We present a more complete formulation that is accurate even when atmospheric temperatures are stable or decreasing due to reductions in short-lived gases or net radiative forcing.
关键词：climate change ; sea-level rise ; greenhouse gases ; reversibility ; Montreal Protocol