气候变化领域集成服务门户(CCPortal): The climate impact of COVID-19-induced contrail changes

CCPortal

DOI	10.5194/acp-21-9405-2021
	The climate impact of COVID-19-induced contrail changes
	Gettelman A.; Chen C.-C.; Bardeen C.G.
发表日期	2021
ISSN	1680-7316
起始页码	9405
结束页码	9416
卷号	21 期号:12
英文摘要	The COVID-19 pandemic caused significant economic disruption in 2020 and severely impacted air traffic. We use a state-of-the-art Earth system model and ensembles of tightly constrained simulations to evaluate the effect of the reductions in aviation traffic on contrail radiative forcing and climate in 2020. In the absence of any COVID-19-pandemic-caused reductions, the model simulates a contrail effective radiative forcing (ERF) of 62±59 mW m-2 (2 standard deviations). The contrail ERF has complex spatial and seasonal patterns that combine the offsetting effect of shortwave (solar) cooling and longwave (infrared) heating from contrails and contrail cirrus. Cooling is larger in June-August due to the preponderance of aviation in the Northern Hemisphere, while warming occurs throughout the year. The spatial and seasonal forcing variations also map onto surface temperature variations. The net land surface temperature change due to contrails in a normal year is estimated at 0.13±0.04 K (2 standard deviations), with some regions warming as much as 0.7 K. The effect of COVID-19 reductions in flight traffic decreased contrails. The unique timing of such reductions, which were maximum in Northern Hemisphere spring and summer when the largest contrail cooling occurs, means that cooling due to fewer contrails in boreal spring and fall was offset by warming due to fewer contrails in boreal summer to give no significant annual averaged ERF from contrail changes in 2020. Despite no net significant global ERF, because of the spatial and seasonal timing of contrail ERF, some land regions would have cooled slightly (minimum-0.2 K) but significantly from contrail changes in 2020. The implications for future climate impacts of contrails are discussed. © 2021 Andrew Gettelman et al.
语种	英语
scopus关键词	air traffic; carbon emission; climate change; climate effect; COVID-19; epidemic; Northern Hemisphere; radiative forcing; shortwave radiation
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/246792
作者单位	Climate and Global Dynamics and Atmospheric Chemistry, Observations and Modeling Laboratories, National Center for Atmospheric Research, Boulder, CO, United States
推荐引用方式 GB/T 7714	Gettelman A.,Chen C.-C.,Bardeen C.G.. The climate impact of COVID-19-induced contrail changes[J],2021,21(12).
APA	Gettelman A.,Chen C.-C.,&Bardeen C.G..(2021).The climate impact of COVID-19-induced contrail changes.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(12).
MLA	Gettelman A.,et al."The climate impact of COVID-19-induced contrail changes".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.12(2021).