DOI: 10.5194/tc-9-1277-2015
Scopus记录号: 2-s2.0-84932612672
论文题名: Parameterization of single-scattering properties of snow
作者: Räisänen P ; , Kokhanovsky A ; , Guyot G ; , Jourdan O ; , Nousiainen T
刊名: Cryosphere
ISSN: 19940416
出版年: 2015
卷: 9, 期: 3 起始页码: 1277
结束页码: 1301
语种: 英语
英文关键词: 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
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. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/75279
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
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作者单位: Finnish Meteorological Institute, P.O. Box 503, Helsinki, Finland; EUMETSAT, Eumetsat Allee 1, Darmstadt, Germany; Institute of Remote Sensing, University of Bremen, Bremen, Germany; Laboratoire de Météorologie Physique (LaMP), Université Blaise Pascal, CNRS, 24 avenue des Landais, Aubiére Cedex, France
Recommended Citation:
Räisänen P,, Kokhanovsky A,, Guyot G,et al. Parameterization of single-scattering properties of snow[J]. Cryosphere,2015-01-01,9(3)