Remote sensing applications in hydrology

The physical basis of remote sensing depends on the inference of land surface characteristics from the measurement of the emitted or reflected electromagnetic radiation from the earth. The hydrologically related parameters studied using this approach include: surface temperature, evapotranspiration, soil moisture precipitation, snow, and components of the radiation balance. Significant progress has been made in determining these quantities using radiation at wavelengths from the microwave to gamma rays. The recent progress in several of these areas will be documented in this review.