气候变化领域集成服务门户(CCPortal): Radiative effects of long-range-transported Saharan air layers as determined from airborne lidar measurements

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DOI	10.5194/acp-20-12313-2020
	Radiative effects of long-range-transported Saharan air layers as determined from airborne lidar measurements
	Gutleben M.; Groß S.; Wirth M.; Mayer B.
发表日期	2020
ISSN	1680-7316
起始页码	12313
结束页码	12327
卷号	20 期号:20
英文摘要	The radiative effect of long-range-transported Saharan air layers is investigated on the basis of simultaneous airborne high-spectral-resolution and differential-absorption lidar measurements in the vicinity of Barbados. Within the observed Saharan air layers, increased water vapor concentrations compared to the dry trade wind atmosphere are found. The measured profiles of aerosol optical properties and water vapor mixing ratios are used to characterize the atmospheric composition in radiative transfer calculations, to calculate radiative effects of moist Saharan air layers and to determine radiative heating rate profiles. An analysis based on three case studies reveals that the observed enhanced amounts of water vapor within Saharan air layers have a much stronger impact on heating rate calculations than mineral dust aerosol. Maximum mineral dust short-wave heating and long-wave cooling rates are found at altitudes of highest dust concentration (short wave: +0.5K d-1 ; long wave: -0.2K d-1 ; net: +0.3K d-1 ). However, when considering both aerosol concentrations and measured water vapor mixing ratios in radiative transfer calculations, the maximum heating/cooling rates shift to the top of the dust layer (short wave: +2.2K d-1 ; long wave: -6.0 to -7.0K d-1 ; net: -4.0 to -5.0K d-1 ). Additionally, the net heating rates decrease with height - indicating a destabilizing effect in the dust layers. Long-wave counter-radiation of Saharan air layers is found to reduce cooling at the tops of the subjacent marine boundary layers and might lead to less convective mixing in these layers. The overall short-wave radiative effect of mineral dust particles in Saharan air layers indicates a maximum magnitude of -40W m-2 at surface level and a maximum of -25W m-2 at the top of the atmosphere. © 2020 Author(s).
语种	英语
scopus关键词	airborne survey; atmospheric transport; concentration (composition); desert; dust; lidar; long range transport; radiative forcing; spectral resolution; water vapor; Barbados
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/247439
作者单位	Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany; Ludwig-Maximilians-Universität (LMU), Meteorologisches Institut, Munich, Germany
推荐引用方式 GB/T 7714	Gutleben M.,Groß S.,Wirth M.,et al. Radiative effects of long-range-transported Saharan air layers as determined from airborne lidar measurements[J],2020,20(20).
APA	Gutleben M.,Groß S.,Wirth M.,&Mayer B..(2020).Radiative effects of long-range-transported Saharan air layers as determined from airborne lidar measurements.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(20).
MLA	Gutleben M.,et al."Radiative effects of long-range-transported Saharan air layers as determined from airborne lidar measurements".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.20(2020).