气候变化领域集成服务门户(CCPortal): Influence of light-absorbing particles on snow spectral irradiance profiles

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DOI	10.5194/tc-13-2169-2019
	Influence of light-absorbing particles on snow spectral irradiance profiles
	Tuzet F.; Dumont M.; Arnaud L.; Voisin D.; Lamare M.; Larue F.; Revuelto J.; Picard G.
发表日期	2019
ISSN	19940416
EISSN	13
起始页码	2169
结束页码	2187
卷号	13 期号:8
英文摘要	Light-absorbing particles (LAPs) such as black carbon or mineral dust are some of the main drivers of snow radiative transfer. Small amounts of LAPs significantly increase snowpack absorption in the visible wavelengths where ice absorption is particularly weak, impacting the surface energy budget of snow-covered areas. However, linking measurements of LAP concentration in snow to their actual radiative impact is a challenging issue which is not fully resolved. In the present paper, we point out a new method based on spectral irradiance profile (SIP) measurements which makes it possible to identify the radiative impact of LAPs on visible light extinction in homogeneous layers of the snowpack. From this impact on light extinction it is possible to infer LAP concentrations present in each layer using radiative transfer theory. This study relies on a unique dataset composed of 26 spectral irradiance profile measurements in the wavelength range 350-950 nm with concomitant profile measurements of snow physical properties and LAP concentrations, collected in the Alps over two snow seasons in winter and spring conditions. For 55 homogeneous snow layers identified in our dataset, the concentrations retrieved from SIP measurements are compared to chemical measurements of LAP concentrations. A good correlation is observed for measured concentrations higher than 5 ng g-1 (r2 0.81) despite a clear positive bias. The potential causes of this bias are discussed, underlining a strong sensitivity of our method to LAP optical properties and to the relationship between snow microstructure and snow optical properties used in the theory. Additional uncertainties such as artefacts in the measurement technique for SIP and chemical contents along with LAP absorption efficiency may explain part of this bias. In addition, spectral information on LAP absorption can be retrieved from SIP measurements. We show that for layers containing a unique absorber, this absorber can be identified in some cases (e.g. mineral dust vs. black carbon). We also observe an enhancement of light absorption between 350 and 650 nm in the presence of liquid water in the snowpack, which is discussed but not fully elucidated. A single SIP acquisition lasts approximately 1 min and is hence much faster than collecting a profile of chemical measurements. With the recent advances in modelling LAP-snow interactions, our method could become an attractive alternative to estimate vertical profiles of LAP concentrations in snow. © 2019 The Author(s).
学科领域	absorption efficiency; black carbon; correlation; energy budget; irradiance; microstructure; mineral dust; particulate matter; radiative transfer; snow cover; snowpack; wavelength
语种	英语
scopus关键词	absorption efficiency; black carbon; correlation; energy budget; irradiance; microstructure; mineral dust; particulate matter; radiative transfer; snow cover; snowpack; wavelength
来源期刊	The Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/118848
作者单位	Univ. Grenoble Alpes, Université de Toulouse, Météo France, CNRS, CNRM, Centre d'Étude de la Neige, Grenoble, France; UGA, CNRS, Institut des Geosciences de l'Environnement (IGE), UMR 5001, Grenoble, France
推荐引用方式 GB/T 7714	Tuzet F.,Dumont M.,Arnaud L.,et al. Influence of light-absorbing particles on snow spectral irradiance profiles[J],2019,13(8).
APA	Tuzet F..,Dumont M..,Arnaud L..,Voisin D..,Lamare M..,...&Picard G..(2019).Influence of light-absorbing particles on snow spectral irradiance profiles.The Cryosphere,13(8).
MLA	Tuzet F.,et al."Influence of light-absorbing particles on snow spectral irradiance profiles".The Cryosphere 13.8(2019).