Correlating Rainfall with Remotely Sensed Microwave Radiation Using Physically Based Models

This simulation study evaluates the response of a 21-cm radiometer, measuring the radiation emitted by a bare soil, to varying accumulations of rain. We show that correlations between the decrease in emissivity after a rain storm and the total accumulation depend strongly on the physical characteristics of the soil which affect its capacity to hold water. These are primarily soil texture and pre-rain soil moisture. A method is also discussed which would use the numerical models with remotely sensed microwave brightness and surface physical temperatures, along with conventional weather data, to estimate the total accumulation.

[1]  Tsan Mo,et al.  A parameterization of effective soil temperature for microwave emission , 1982 .

[2]  Ray D. Jackson,et al.  Diurnal Changes in Soil Water Content During Drying , 1973 .

[3]  Thomas J. Schmugge Effect of Texture on Microwave Emission from Soils , 1980, IEEE Transactions on Geoscience and Remote Sensing.

[4]  G. Hornberger,et al.  Empirical equations for some soil hydraulic properties , 1978 .

[5]  Eni G. Njoku,et al.  Multifrequency Microwave Radiometer Measurements of Soil Moisture , 1982, IEEE Transactions on Geoscience and Remote Sensing.

[6]  T. Schmugge Remote Sensing of Surface Soil Moisture , 1978 .

[7]  W. J. Burke,et al.  Comparison of 2.8‐ and 21‐cm microwave radiometer observations over soils with emission model calculations , 1979 .

[8]  R. Newton,et al.  Microwave radiometer measurements of soil moisture content , 1980 .

[9]  Thomas Wilheit,et al.  Radiative Transfer in a Plane Stratified Dielectric , 1975, IEEE Transactions on Geoscience Electronics.

[10]  T. Schmugge,et al.  An Empirical ModelfortheComplexDielectric Permittivity ofSoils as a Function of WaterContent , 1980 .

[11]  Thomas J. Schmugge,et al.  A soil and atmospheric boundary layer model for evapotranspiration and soil moisture studies , 1983 .

[12]  R. J. Gurney,et al.  Modelling daily evapotranspiration using remotely sensed data , 1984 .

[13]  J. Kong,et al.  Theory for passive microwave remote sensing of near‐surface soil moisture , 1977 .

[14]  R. J. Gurney,et al.  A Sensitivity Analysis of a Numerical Model for Estimating Evapotranspiration , 1984 .

[15]  G.J.R. Soer Estimation of regional evapotranspiration and soil moisture conditions using remotely sensed crop surface temperatures , 1980 .

[16]  Thomas J. Schmugge,et al.  Estimation of Soil Moisture with Api Algorithms and Microwave Emission , 1981 .

[17]  J. R. Philip,et al.  Moisture movement in porous materials under temperature gradients , 1957 .

[18]  Bhaskar J. Choudhury,et al.  Simulating Soil Water Recession Coefficients for Agricultural Watersheds , 1983 .