An Efficient Downscaling Scheme for High-Resolution Precipitation Estimates over a High Mountainous Watershed

doi:10.3390/rs13020234

	An Efficient Downscaling Scheme for High-Resolution Precipitation Estimates over a High Mountainous Watershed
	Zhao, Na 1,2,3
刊名	REMOTE SENSING
	2021
卷号	13 期号:2 页码:18
关键词	satellite precipitation product statistical downscaling rain gauge IMERG
DOI	10.3390/rs13020234
通讯作者	Zhao, Na(zhaon@lreis.ac.cn)
英文摘要	Satellites are capable of observing precipitation over large areas and are particularly suitable for estimating precipitation in high mountains and poorly gauged regions. However, the coarse resolution and relatively low accuracy of satellites limit their applications. In this study, a downscaling scheme was developed to obtain precipitation estimates with high resolution and high accuracy in the Heihe watershed. Shannon's entropy, together with a semi-variogram, was applied to establish the optimal precipitation station network. A combination of the random forest (RF) method and the residual correction approach with the established rain gauge network was applied to downscale monthly precipitation products from Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG). The results indicated that the RF model showed little improvement in the accuracy of IMERG-based precipitation downscaling. Including residual modification could improve the results of the RF model. The mean absolute error (MAE) and root mean square error (RMSE) values decreased by 19% and 21%, respectively, after residual corrections were added to the RF approach. Moreover, we found that enough rain gauge records are necessary for and remain an important component of tuning model performance. The application of more rain gauges improves the performance of the combined RF and residual modification methods, with the MAE and RMSE values reduced by 8% and 9%, respectively. Residual correction, together with enough precipitation stations, can effectively enhance the quality of the precipitation patterns and magnitudes obtained in the RF downscaling process. The proposed downscaling scheme is an effective tool for increasing the accuracy and spatial resolution of precipitation fields in the Heihe watershed.
资助项目	National Natural Science Foundation of China[42071374] ; Program of Frontier Sciences of Chinese Academy of Sciences[ZDBS-LY-DQC005]
WOS研究方向	Environmental Sciences & Ecology ; Geology ; Remote Sensing ; Imaging Science & Photographic Technology
语种	英语
出版者	MDPI
WOS记录号	WOS:000611552200001
资助机构	National Natural Science Foundation of China ; Program of Frontier Sciences of Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/160697]
专题	中国科学院地理科学与资源研究所
通讯作者	Zhao, Na
作者单位	1.Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China 2.Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100101, Peoples R China 3.Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Peoples R China
推荐引用方式 GB/T 7714	Zhao, Na. An Efficient Downscaling Scheme for High-Resolution Precipitation Estimates over a High Mountainous Watershed[J]. REMOTE SENSING,2021,13(2):18.
APA	Zhao, Na.(2021).An Efficient Downscaling Scheme for High-Resolution Precipitation Estimates over a High Mountainous Watershed.REMOTE SENSING,13(2),18.
MLA	Zhao, Na."An Efficient Downscaling Scheme for High-Resolution Precipitation Estimates over a High Mountainous Watershed".REMOTE SENSING 13.2(2021):18.