气候变化领域集成服务门户(CCPortal): Estimation of Snow Depth over the Qinghai-Tibetan Plateau Based on AMSR-E and MODIS Data

CCPortal

DOI	10.3390/rs10121989
	Estimation of Snow Depth over the Qinghai-Tibetan Plateau Based on AMSR-E and MODIS Data
	Dai, Liyun; Che, Tao; Xie, Hongjie; Wu, Xuejiao
发表日期	2018
ISSN	2072-4292
卷号	10 期号:12
英文摘要	Snow cover over the Qinghai-Tibetan Plateau (QTP) plays an important role in climate, hydrological, and ecological systems. Currently, passive microwave remote sensing is the most efficient way to monitor snow depth on global and regional scales; however, it presents a serious overestimation of snow cover over the QTP and has difficulty describing patchy snow cover over the QTP because of its coarse spatial resolution. In this study, a new spatial dynamic method is developed by introducing ground emissivity and assimilating the snow cover fraction (SCF) and land surface temperature (LST) of the Moderate Resolution Imaging Spectroradiometer (MODIS) to derive snow depth at an enhanced spatial resolution. In this method, the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) brightness temperature and MODIS LST are used to calculate ground emissivity. Additionally, the microwave emission model of layered snowpacks (MEMLS) is applied to simulate brightness temperature with varying ground emissivities to determine the key coefficients in the snow depth retrieval algorithm. The results show that the frozen ground emissivity presents large spatial heterogeneity over the QTP, which leads to the variation of coefficients in the snow depth retrieval algorithm. The overestimation of snow depth is rectified by introducing the ground emissivity factor at 18 and 36 GHz. Compared with in situ observations, the snow cover accuracy of the new method is 93.9%, which is better than the 60.2% accuracy of the existing method (old method) which does not consider ground emissivity. The bias and root-mean-square error (RMSE) of snow depth are 1.03 cm and 7.05 cm, respectively, for the new method; these values are much lower than the values of 6.02 cm and 9.75 cm, respectively, for the old method. However, the snow cover accuracy with depths between 1 and 3 cm is below 60%, and snow depths greater than 25 cm are underestimated in Himalayan mountainous areas. In the future, the snow cover identification algorithm should be improved to identify shallow snow cover over the QTP, and topography should be considered in the snow depth retrieval algorithm to improve snow depth accuracy in mountainous areas.
英文关键词	snow depth; passive microwave; Qinghai-Tibetan Plateau; emissivity; land surface temperature; snow cover fraction; snow depletion curve
WOS研究方向	Environmental Sciences & Ecology ; Geology ; Remote Sensing ; Imaging Science & Photographic Technology
WOS类目	Environmental Sciences ; Geosciences, Multidisciplinary ; Remote Sensing ; Imaging Science & Photographic Technology
WOS关键词	EQUIVALENT RETRIEVAL ALGORITHMS ; PASSIVE MICROWAVE DATA ; WATER EQUIVALENT ; RADIOMETER DATA ; CLOUD MASK ; COVER ; MODEL ; ASSIMILATION ; HYDROLOGY ; EMISSION
WOS记录号	WOS:000455637600131
来源期刊	REMOTE SENSING
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/241032
作者单位	[Dai, Liyun; Che, Tao] Chinese Acad Sci, Key Lab Remote Sensing Gansu Prov, Heihe Remote Sensing Expt Res Stn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China; [Che, Tao] Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China; [Dai, Liyun; Xie, Hongjie] Univ Texas San Antonio, Dept Geol Sci, Lab Remote Sensing & Geoinformat, San Antonio, TX 78249 USA; [Dai, Liyun] Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 21003, Jiangsu, Peoples R China; [Wu, Xuejiao] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China
推荐引用方式 GB/T 7714	Dai, Liyun,Che, Tao,Xie, Hongjie,et al. Estimation of Snow Depth over the Qinghai-Tibetan Plateau Based on AMSR-E and MODIS Data[J]. 中国科学院西北生态环境资源研究院,2018,10(12).
APA	Dai, Liyun,Che, Tao,Xie, Hongjie,&Wu, Xuejiao.(2018).Estimation of Snow Depth over the Qinghai-Tibetan Plateau Based on AMSR-E and MODIS Data.REMOTE SENSING,10(12).
MLA	Dai, Liyun,et al."Estimation of Snow Depth over the Qinghai-Tibetan Plateau Based on AMSR-E and MODIS Data".REMOTE SENSING 10.12(2018).