New dimensions in satellite hydrology



Remote sensing technology applied from satellites and aircraft can and should be a very useful tool in obtaining information for the rapid and continuing assessment of the hydrologic cycle. However, until the second half of 1972, most water resources studies employing satellites were limited to large areas (because of the low resolution of the sensors on the available meteorological satellites), over which only gross hydrologic relationships could be inferred. Moreover, the wavelength bands sensed by these satellites were usually designed to observe meteorological features (i.e., clouds and atmospheric moisture) and not to discriminate among subtle terrain variations.