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DOI	10.5194/tc-9-1277-2015
	Parameterization of single-scattering properties of snow
	Räisänen P.; Kokhanovsky A.; Guyot G.; Jourdan O.; Nousiainen T.
发表日期	2015
ISSN	19940416
卷号	9 期号:3
英文摘要	Snow consists of non-spherical grains of various shapes and sizes. Still, in many radiative transfer applications, single-scattering properties of snow have been based on the assumption of spherical grains. More recently, second-generation Koch fractals have been employed. While they produce a relatively flat phase function typical of deformed non-spherical particles, this is still a rather ad hoc choice. Here, angular scattering measurements for blowing snow conducted during the CLimate IMpacts of Short-Lived pollutants In the Polar region (CLIMSLIP) campaign at Ny Ålesund, Svalbard, are used to construct a reference phase function for snow. Based on this phase function, an optimized habit combination (OHC) consisting of severely rough (SR) droxtals, aggregates of SR plates and strongly distorted Koch fractals is selected. The single-scattering properties of snow are then computed for the OHC as a function of wavelength λ and snow grain volume-to-projected area equivalent radius rvp. Parameterization equations are developed for λ = 0.199-2.7 μm and rvp = 10-2000 μm, which express the single-scattering co-albedo β, the asymmetry parameter g and the phase function P11 as functions of the size parameter and the real and imaginary parts of the refractive index. The parameterizations are analytic and simple to use in radiative transfer models. Compared to the reference values computed for the OHC, the accuracy of the parameterization is very high for β and g. This is also true for the phase function parameterization, except for strongly absorbing cases (β > 0.3). Finally, we consider snow albedo and reflected radiances for the suggested snow optics parameterization, making comparisons to spheres and distorted Koch fractals. © Author(s) 2015.
学科领域	albedo; climate effect; fractal analysis; parameterization; polar region; pollutant transport; radiative transfer; refractive index; snow; wavelength; Arctic; Ny-Alesund; Spitsbergen; Svalbard; Svalbard and Jan Mayen
语种	英语
scopus关键词	albedo; climate effect; fractal analysis; parameterization; polar region; pollutant transport; radiative transfer; refractive index; snow; wavelength; Arctic; Ny-Alesund; Spitsbergen; Svalbard; Svalbard and Jan Mayen
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119879
作者单位	Finnish Meteorological Institute, P.O. Box 503, Helsinki, 00101, Finland; EUMETSAT, Eumetsat Allee 1, Darmstadt, 64295, Germany; Institute of Remote Sensing, University of Bremen, Bremen, 28334, Germany; Laboratoire de Météorologie Physique (LaMP), Université Blaise Pascal, CNRS, 24 avenue des Landais, Aubiére Cedex, 63177, France
推荐引用方式 GB/T 7714	Räisänen P.,Kokhanovsky A.,Guyot G.,et al. Parameterization of single-scattering properties of snow[J],2015,9(3).
APA	Räisänen P.,Kokhanovsky A.,Guyot G.,Jourdan O.,&Nousiainen T..(2015).Parameterization of single-scattering properties of snow.Cryosphere,9(3).
MLA	Räisänen P.,et al."Parameterization of single-scattering properties of snow".Cryosphere 9.3(2015).