This book shows you how to use microwave radiometry to monitor processes in the earth?s environment and to estimate properties of planetary surfaces and atmospheres. It uses simple MATLAB models to illustrate the radiant processes of emission, propagation, scattering, and absorption; to introduce techniques for inverting observational data to obtain estimates of environmental state; and to understand the interpretive constraints imposed by radiometer performance. The author focuses on achieving an intuitive understanding of relevant physical and interpretive processes.