标题:Evaluation of Multiple Downscaled Microwave Soil Moisture Products over the Central Tibetan Plateau作者:Jiang, HT (Jiang, Hongtao); Shen, HF (Shen, Huanfeng); Li, HF (Li, Huifang); Lei, FN (Lei, Fangni); Gan, WX (Gan, Wenxia); Zhang, LP (Zhang, Liangpei)
来源出版物:REMOTE SENSING卷:9 期:5文献编号:402 DOI:10.3390/rs9050402 出版年:MAY 2007
摘要:Downscaled microwave soil moisture (SM) products with a fine resolution are of great importance for both local and regional studies. However, few studies have explored the merits of multiple downscaled microwave SM products. An evaluation of the different products could help to advance knowledge of the downscaled microwave SM products and help researchers to choose the appropriate downscaled SM products for use in further studies. In this research, five microwave SM products derived from Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E), AMSR2, and Soil Moisture and Ocean Salinity (SMOS) data were downscaled via the back-propagation neural network (BPNN). The BPNN was chosen because it can effectively simulate the nonlinear relationship between SM and the land surface temperature (LST)/vegetation index (VI). The different downscaled SM products were evaluated with in-situ SM data from the central Tibetan Plateau Soil Moisture/Temperature Monitoring Network (SMTMN) during the period from 1 August 2010 to 31 December 2012. Compared with the regression technique, the downscaled correlation coefficient (r) is significantly improved by the BPNN. The downscaled root-mean-square error (RMSE) and bias are comparable for the two techniques. As expected, LST and enhanced VI (EVI) are physically related to SM, and this is the most suitable combination for SM downscaling. Except for the ascending node of SMOS and AMSR2, the downscaled r is closely related to the original RMSE, and a lower original RMSE for the SM product results in a higher downscaled r. The BPNN-downscaled SMOS product in descending node is the closest to the in-situ SM among the different downscaled microwave SM products. The temporal variations and ranges of the microwave SM products are well maintained by the BPNN downscaling. Furthermore, the evaluations against in-situ SM reveal that the overall accuracies of the BPNN-downscaled SM products are very close to the original microwave SM products.
入藏号:WOS:000402573700005
文献类型:Article
语种:English
作者关键词: evaluation; downscaling; back-propagation neural network (BPNN); passive microwave soil moisture products
扩展关键词: IMPROVING SPATIAL REPRESENTATION; LAND DATA ASSIMILATION; AMSR-E; HIGH-RESOLUTION; MODIS PRODUCTS; SMOS; VEGETATION; INTEGRATION; DISAGGREGATION; ALGORITHM
通讯作者地址:Shen, HF (reprint author), Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430079, Peoples R China.
电子邮件地址: htj@whu.edu.cn; shenhf@whu.edu.cn; huifangli@whu.edu.cn; leifangni@whu.edu.cn; charlottegan@whu.edu.cn; zlp62@whu.edu.cn
地址:
[Jiang, Hongtao; Shen, Huanfeng; Li, Huifang; Lei, Fangni] Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430079, Peoples R China.
[Gan, Wenxia] Wuhan Inst Technol, Sch Resource & Civil Engn, Wuhan 430205, Peoples R China.
[Zhang, Liangpei] Wuhan Univ, State Key Lab Informat Engn Surveying Mapping & R, Wuhan 430079, Peoples R China.
研究方向:Remote Sensing
ISSN:2072-4292
影响因子:3.244
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