Gaussian process regression algorithm based method for merging daily-scale IMERG and gauge precipitation data: a case of Hubei Province
TAN Weiwei1, ZENG Chao2, SHEN Huanfeng2,3,4, TIAN Liqiao1
1.State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University Wuhan 430079, China;2.School of Resource and Environmental Sciences, Wuhan University Wuhan 430079, China;3.Collaborative Innovation Center of Geospatial Technology, Wuhan 430079, China;4.Key Laboratory of Geographic Information System, Ministry of Education, Wuhan 430079, China
Abstract:This paper focuses on the low spatial resolution of satellite precipitation data. The daily IMERG satellite precipitation data with rain gauge data are merged on July 19, 2016 and auxiliary variables, such as longitude, latitude, DEM, brightness temperature data, and interpolation data, are considered. Taking the Hubei Province as the study area, in this paper, two fusion schemes, point-to-surface fusion method and bias-correction fusion method, are proposed. Three algorithms are selected including adaptive spline multiple regression, random forest and Gaussian process regression. The results show that the point-surface fusion method is superior to the bias-correction fusion method, and the fusion results by Gaussian process regression are better than other two algorithms. The fusion results based on the Gaussian process method show reasonable change details, which accord with the spatial pattern of precipitation. The spatial resolution of the fusion result has been improved from 0.1°(about 10 km) to 1 km, and the accuracy has been greatly improved compared to the original IMERG data. This research has certain significance for the fusion of multi-source precipitation data with high temporal resolution.
谭伟伟,曾 超,沈焕锋,田礼乔. 基于高斯过程算法的日尺度IMERG降水数据与站点数据的融合研究——以湖北省为例[J]. 华中师范大学学报(自然科学版), 2020, 54(3): 439-446.
TAN Weiwei,ZENG Chao,SHEN Huanfeng,TIAN Liqiao. Gaussian process regression algorithm based method for merging daily-scale IMERG and gauge precipitation data: a case of Hubei Province. journal1, 2020, 54(3): 439-446.