气候变化领域集成服务门户(CCPortal): Anisotropy of seasonal snow measured by polarimetric phase differences in radar time series

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DOI	10.5194/tc-10-1771-2016
	Anisotropy of seasonal snow measured by polarimetric phase differences in radar time series
	Leinss S.; Löwe H.; Proksch M.; Lemmetyinen J.; Wiesmann A.; Hajnsek I.
发表日期	2016
ISSN	19940416
卷号	10 期号:4
英文摘要	The snow microstructure, i.e., the spatial distribution of ice and pores, generally shows an anisotropy which is driven by gravity and temperature gradients and commonly determined from stereology or computer tomography. This structural anisotropy induces anisotropic mechanical, thermal, and dielectric properties. We present a method based on radio-wave birefringence to determine the depth-averaged, dielectric anisotropy of seasonal snow with radar instruments from space, air, or ground. For known snow depth and density, the birefringence allows determination of the dielectric anisotropy by measuring the copolar phase difference (CPD) between linearly polarized microwaves propagating obliquely through the snowpack. The dielectric and structural anisotropy are linked by Maxwell- Garnett-type mixing formulas. The anisotropy evolution of a natural snowpack in Northern Finland was observed over four winters (2009-2013) with the ground-based radar instrument "SnowScat". The radar measurements indicate horizontal structures for fresh snow and vertical structures in old snow which is confirmed by computer tomographic in situ measurements. The temporal evolution of the CPD agreed in ground-based data compared to space-borne measurements from the satellite TerraSAR-X. The presented dataset provides a valuable basis for the development of new snow metamorphism models which include the anisotropy of the snow microstructure. © Author(s) 2016.
学科领域	anisotropy; birefringence; in situ measurement; microstructure; radar interferometry; snow; snowpack; spatial distribution; temporal evolution; TerraSAR-X; time series analysis; tomography; Finland
语种	英语
scopus关键词	anisotropy; birefringence; in situ measurement; microstructure; radar interferometry; snow; snowpack; spatial distribution; temporal evolution; TerraSAR-X; time series analysis; tomography; Finland
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/119601
作者单位	Institute of Environmental Engineering, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland; Institute for Snow and Avalanche Research SLF, Davos, Switzerland; Finnish Meteorological Institute FMI, Arctic Research, Sodankylä, Finland; GAMMA Remote Sensing AG, Gümlingen, Switzerland; Microwaves and Radar Institute, German Aerospace Center (DLR), Wessling, Germany
推荐引用方式 GB/T 7714	Leinss S.,Löwe H.,Proksch M.,et al. Anisotropy of seasonal snow measured by polarimetric phase differences in radar time series[J],2016,10(4).
APA	Leinss S.,Löwe H.,Proksch M.,Lemmetyinen J.,Wiesmann A.,&Hajnsek I..(2016).Anisotropy of seasonal snow measured by polarimetric phase differences in radar time series.Cryosphere,10(4).
MLA	Leinss S.,et al."Anisotropy of seasonal snow measured by polarimetric phase differences in radar time series".Cryosphere 10.4(2016).