Estimating root zone soil moisture from surface soil moisture data and soil-vegetation-atmosphere transfer modeling

We studied the possibility of estimating root zone soil moisture through th e combined use of a time series of observed surface soil moisture data and soil-vegetation-atmosphere transfer modeling. The analysis was based on the interactions between soil-biosphere-atmosphere surface scheme and two data sets obtained from soybean crops in 1989 and 1990. These data sets include d detailed measurements of soil and vegetation characteristics and mass and energy transfer in the soil-plant-atmosphere system. The data measured dur ing the 3-month experiment in 1989 are used to investigate the accuracy of soil reservoir retrievals, as a function of the time period and frequency o f measurements of surface soil moisture involved in the retrieval process. This study contributes to better defining the requirements for the use, of remotely sensed microwave measurements of surface soil moisture.