Measuring soil moisture

Abstract

A recent aerial field experiment of the National Aeronautics and Space Administration carried out above farmland near Ames, Iowa, could help scientists to develop a remote global soil moisture observing system over most of the Earth's non‐forested and unfrozen regions.During the experiment, which lasted from 25 June to 8 July scientists and engineers measured soil moisture content with remote sensing techniques that included a passive and active L‐ and S‐band microwave instrument about 1.1 kilometers above ground, and an airborne synthetic aperture radar flying at an altitude of about 7.9 kilometers.