QQ客服 官方微博 反馈留言

	Estimation and analysis of snow water equivalents based on C-band SAR data and field measurements
	Sun S. B.; Che, T.; Wang, J.; Li, H. Y.; Hao, X. H.; Wang, Z. Y.
	2015
关键词	microwave dielectric behavior eastern canada wet soil backscatter cover depth scattering parameters signatures surface
英文摘要	The spatial distribution of the snow water equivalent (SWE) of ground snow cover is one of the most important variables for understanding and simulating cold-region hydrological processes in high mountain areas. In this paper, the characteristics of C-band synthetic aperture radar (SAR) data in an area of shallow dry snow cover were analyzed based on microwave backscattering models and field snow cover measurements. The analysis revealed that the backscattering of shallow dry snow cover was dominated by the scattering of the snow-ground interface, and the dielectric constant and roughness parameters of the underlying frozen soil were the primary factors that affected the total scattering. The dielectric constant of the soil depended on the amount of liquid water present in the soil, and the amount of liquid water was primarily determined by the soil temperature. Furthermore, the insulation properties (thermal resistance) of the snow cover affected the underlying soil temperature. Consequently, the snow cover characteristics affected the backscattering signal recorded by the SAR sensors. Based on an investigation involving ENVISAT-ASAR data and simultaneous ground-based snow observations conducted on 14 March 2008, we found that the snow temperature decreased with increasing snow depth when the snow depth was less than 20 cm, and the temperature increased with decreasing snow depth when the snow depth exceeded 20 cm. Additionally, the amount of liquid water in the underlying frozen soil rapidly increased with increasing temperature. To estimate the SWE, we used a small number of field measurements data and SAR ratio images to develop two equations. The first equation defined the relationship between the snow's thermal resistance and backscattering ratio, and the second equation yielded the SWE from the estimated thermal resistance of the snow-covered area. The root mean square and relative errors of the estimated SWE were approximately 7.41 mm and 6.17%, respectively. The derived SWE also indicated that blowing snow and sun radiation were two primary factors that determined the spatial distribution of snow cover in mountainous areas.
出处	Arctic Antarctic and Alpine Research
卷	47
期	2
页	313-326
收录类别	SCI
语种	英语
ISSN号	1523-0430
内容类型	SCI/SSCI论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/38481]
专题	地理科学与资源研究所_历年回溯文献
推荐引用方式 GB/T 7714	Sun S. B.,Che, T.,Wang, J.,et al. Estimation and analysis of snow water equivalents based on C-band SAR data and field measurements. 2015.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。