气候变化领域集成服务门户(CCPortal): Contrasting Observed Atmospheric Responses to Tropical Sea Surface Temperature Warming Patterns

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DOI	10.1029/2020JD033564
	Contrasting Observed Atmospheric Responses to Tropical Sea Surface Temperature Warming Patterns
	Mackie A.; Brindley H.E.; Palmer P.I.
发表日期	2021
ISSN	2169897X
卷号	126 期号:7
英文摘要	Equilibrium climate sensitivity (ECS) is a theoretical concept which describes the change in global mean surface temperature that results from a sustained doubling of atmospheric CO2. Current ECS estimates range from ∼1.8 to 5.6 K, reflecting uncertainties in climate feedbacks. The sensitivity of the lower (1,000–700 hPa) and upper (500–200 hPa) troposphere to changes in spatial patterns of tropical sea surface temperature (SST) have been proposed by recent model studies as key feedbacks controlling climate sensitivity. We examine empirical evidence for these proposed mechanisms using 14 years of satellite data. We examine the response of temperature and humidity profiles, clouds, and top-of-the-atmosphere radiation to relative warming in tropical ocean regions when there is either strong convection or subsidence. We find warmer SSTs in regions of strong subsidence are coincident with a decrease in lower tropospheric stability (−0.9 ± 0.4 KK−1) and low cloud cover (∼−6% K−1). This leads to a warming associated with the weakening in the shortwave cooling effect of clouds (4.2 ± 1.9 Wm−2K−1), broadly consistent with model calculations. In contrast, warmer SSTs in regions of strong convection are coincident with an increase in upper tropospheric humidity (3.2 ± 1.5% K−1). In this scenario, the dominant effect is the enhancement of the warming longwave cloud radiative effect (3.8 ± 3.0 Wm−2K−1) from an increase in high cloud cover (∼7% K−1), though changes in the net (longwave and shortwave) effect are not statistically significant (p < 0.003). Our observational evidence supports the existence of mechanisms linking contrasting atmospheric responses to patterns in SST, mechanisms which have been linked to climate sensitivity. © 2021. The Authors.
英文关键词	climate sensitivity; satellite observations; SST warming patterns; tropical atmosphere
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185348
作者单位	School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom; Space and Atmospheric Physics Group, Imperial College London, London, United Kingdom; National Centre for Earth Observation, Imperial College London, London, United Kingdom; National Centre for Earth Observation, University of Edinburgh, Edinburgh, United Kingdom; Now at the University of St Andrews, St Andrews, United Kingdom
推荐引用方式 GB/T 7714	Mackie A.,Brindley H.E.,Palmer P.I.. Contrasting Observed Atmospheric Responses to Tropical Sea Surface Temperature Warming Patterns[J],2021,126(7).
APA	Mackie A.,Brindley H.E.,&Palmer P.I..(2021).Contrasting Observed Atmospheric Responses to Tropical Sea Surface Temperature Warming Patterns.Journal of Geophysical Research: Atmospheres,126(7).
MLA	Mackie A.,et al."Contrasting Observed Atmospheric Responses to Tropical Sea Surface Temperature Warming Patterns".Journal of Geophysical Research: Atmospheres 126.7(2021).