Surface Soil Moisture Retrieval from the Temporal Evolution of Surface Temperature for Bare Surface
Land surface soil moisture(SSM)has an important role for groundwater recharge,agriculture,soil chemistry,and climate forecasting.Many recent scientific research efforts have aimed toward a predictive-understanding of SSM over space and time based on the instantaneous observations of land surface temperature(LST).However,the information provided by the temporal variation of LST has been less considered or discussed.The present study aims to find the relationship between the temporal variation of LST and SSM and then to propose a method for retrieving SSM from geostationary satellite data.Due to the absence of the accurate SSM measurements at large scale,NOAH land surface model(LSM)is used to provide the temporal evolution of the LST under different soil types and SSM conditions for cloud free days and bare soil surfaces.Two empirical models(linear and second-degree polynomial forms)are proposed to estimate SSM using the two LST temporal variables TN(the LST rising rate normalized by the difference in the net surface shortwave radiation during the mid-morning)and td(the time at which the daily maximum temperature occurs).The root mean square errors(RMSE)of the SSM retrieved using the linear and second-degree models with simulated data are found to be 0.03m3/m3 and 0.024m3/m3 respectively.The results show that the coefficients except for the constant term in both models are independent of the atmospheric conditions and soil types,but the constant term varies with atmospheric forcing data.This study indicates that the SSM of bare soil surfaces can be estimated with high accuracy if the constant term is obtained or estimated accurately.
Wei Zhao Zhao-Liang Li
State Key Laboratory of Resources and Environment Information System Institute of Geographical Scien State Key Laboratory of Resources and Environment Information System Institute of Geographical Scien
国际会议
Progress in Electromagnetics Research Symposium 2011(2011年电磁学研究新进展学术研讨会)
苏州
英文
359-363
2011-09-01（万方平台首次上网日期，不代表论文的发表时间）