气候变化领域集成服务门户(CCPortal): Analyzing the arctic feedback mechanism between sea ice and low-level clouds using 34 years of satellite observations

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DOI	10.1175/JCLI-D-19-0895.1
	Analyzing the arctic feedback mechanism between sea ice and low-level clouds using 34 years of satellite observations
	Philipp D.; Stengel M.; Ahrens B.
发表日期	2020
ISSN	0894-8755
起始页码	7479
结束页码	7501
卷号	33 期号:17
英文摘要	Satellite-based cloud, radiation flux, and sea ice records covering 34 years are used 1) to investigate autumn cloud cover trends over the Arctic, 2) to assess its relation with declining sea ice using Granger causality (GC) analysis, and 3) to discuss the contribution of the cloud–sea ice (CSI) feedback to Arctic amplification. This paper provides strong evidence for a positive CSI feedback with the capability to contribute to autumnal Arctic amplification. Positive low-level cloud fractional cover (CFClow) trends over the Arctic ice pack are found in October and November (ON) with magnitudes of up to about 19.6% per decade locally. Statistically significant anticorrelations between sea ice concentration (SIC) and CFClow are observed in ON over melting zones, suggesting an association. The GC analysis indicated a causal two-way interaction between SIC and CFClow. Interpreting the resulting F statistic and its spatial distribution as a relation strength proxy, the influence of SIC on CFClow is likely stronger than the reverse. ERA-Interim reanalysis data suggest that ON CFClow is impacted by sea ice melt through surface–atmosphere coupling via turbulent heat and moisture fluxes. Due to weak solar insolation in ON, net cloud radiative forcing (CRF) exerts a warming effect on the Arctic surface. Increasing CFClow induces a large-scale surface warming trend reaching magnitudes of up to about 18.3 W m22 per decade locally. Sensitivities of total CRF to CFClow ranges between 10.22 and 10.66 W m22 per percent CFClow. Increasing surface warming can cause a melt season lengthening and hinders formation of perennial ice. Ó 2020 American Meteorological Society.
英文关键词	Atmospheric radiation; American meteorological societies; Cloud radiative forcing; Feedback mechanisms; Granger Causality; Satellite observations; Sea ice concentration; Solar insolation; Two-way interaction; Sea ice; cloud radiative forcing; feedback mechanism; heat flux; moisture flux; satellite imagery; sea ice; Arctic
语种	英语
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/171151
作者单位	Deutscher Wetterdienst, Offenbach am Main, Germany; Institute for Atmospheric and Environmental Sciences, Goethe University, Frankfurt am Main, Germany
推荐引用方式 GB/T 7714	Philipp D.,Stengel M.,Ahrens B.. Analyzing the arctic feedback mechanism between sea ice and low-level clouds using 34 years of satellite observations[J],2020,33(17).
APA	Philipp D.,Stengel M.,&Ahrens B..(2020).Analyzing the arctic feedback mechanism between sea ice and low-level clouds using 34 years of satellite observations.Journal of Climate,33(17).
MLA	Philipp D.,et al."Analyzing the arctic feedback mechanism between sea ice and low-level clouds using 34 years of satellite observations".Journal of Climate 33.17(2020).