Comprehensive Error Analysis of CLDAS Soil Moisture Over Arid and Semiarid Regions

Abstract

Soil moisture (SM) is an important parameter in all environments because it affects the relationship between the land surface and atmospheric processes. Therefore, finding products that can accurately measure SM is critical to improving drought management. The objective of this study was to investigate the accuracy of satellite data from SM produced by the China Meteorological Administration Land Data Assimilation System (CLDAS), focusing on the Huaihe and Heihe River basins in China, as both are prone to drought. To verify the accuracy of the daily surface data SM, measurements were obtained from 34 meteorological stations between January and December 2016. In addition, CLDAS measurement data were collected at a depth of 10 cm and 40 cm and compared with observed soil moisture measurements (OBS SM). The results show that the agreement of CLDAS SM with OBS was R > 0.66 at 10 cm and R > 0.47 at 40 cm in the Huaihe River Basin. R > 0.63 at 10 cm and R > 0.44 at 40 cm was observed in Heihe River Basin.

Keywords

• China Meteorological Administration Land Data Assimilation System (CLDAS)
• observation soil moisture (OBS SM)
• remote sensing
• spatial and temporal variation