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DOI	10.1073/pnas.1708980114
	On transient climate change at the Cretaceous−Paleogene boundary due to atmospheric soot injections
	Bardeen C.G.; Garcia R.R.; Toon O.B.; Conley A.J.
发表日期	2017
ISSN	0027-8424
起始页码	E7415
结束页码	E7424
卷号	114 期号:36
英文摘要	Climate simulations that consider injection into the atmosphere of 15,000 Tg of soot, the amount estimated to be present at the Cretaceous−Paleogene boundary, produce what might have been one of the largest episodes of transient climate change in Earth history. The observed soot is believed to originate from global wildfires ignited after the impact of a 10-km-diameter asteroid on the Yucatán Peninsula 66 million y ago. Following injection into the atmosphere, the soot is heated by sunlight and lofted to great heights, resulting in a worldwide soot aerosol layer that lasts several years. As a result, little or no sunlight reaches the surface for over a year, such that photosynthesis is impossible and continents and oceans cool by as much as 28 °C and 11 °C, respectively. The absorption of light by the soot heats the upper atmosphere by hundreds of degrees. These high temperatures, together with a massive injection of water, which is a source of odd-hydrogen radicals, destroy the stratospheric ozone layer, such that Earth’s surface receives high doses of UV radiation for about a year once the soot clears, five years after the impact. Temperatures remain above freezing in the oceans, coastal areas, and parts of the Tropics, but photosynthesis is severely inhibited for the first 1 y to 2 y, and freezing temperatures persist at middle latitudes for 3 y to 4 y. Refugia from these effects would have been very limited. The transient climate perturbation ends abruptly as the stratosphere cools and becomes supersaturated, causing rapid dehydration that removes all remaining soot via wet deposition. © 2017, National Academy of Sciences. All rights reserved.
英文关键词	Asteroid impact; Chicxulub; Cretaceous; Extinction; Soot
语种	英语
scopus关键词	hydrogen; radical; water; aerosol; Article; atmosphere; climate change; Cretaceous; environmental temperature; freezing; high temperature; latitude; light absorption; ozone layer; Paleogene; photosynthesis; priority journal; sea; simulation; soot; stratosphere; sunlight; ultraviolet radiation; wet deposition; Yucatan
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160601
作者单位	Bardeen, C.G., Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO 80307, United States; Garcia, R.R., Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO 80307, United States; Toon, O.B., Laboratory for Atmospheric and Space Physics, Department of Atmospheric and Ocean Sciences, University of Colorado at Boulder, Boulder, CO 80303, United States; Conley, A.J., Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO 80307, United States
推荐引用方式 GB/T 7714	Bardeen C.G.,Garcia R.R.,Toon O.B.,et al. On transient climate change at the Cretaceous−Paleogene boundary due to atmospheric soot injections[J],2017,114(36).
APA	Bardeen C.G.,Garcia R.R.,Toon O.B.,&Conley A.J..(2017).On transient climate change at the Cretaceous−Paleogene boundary due to atmospheric soot injections.Proceedings of the National Academy of Sciences of the United States of America,114(36).
MLA	Bardeen C.G.,et al."On transient climate change at the Cretaceous−Paleogene boundary due to atmospheric soot injections".Proceedings of the National Academy of Sciences of the United States of America 114.36(2017).