Abstract
The rarity of rainfall, and its broad and varied significance, are affirmed, followed by a review of the problems of rainfall measurement and monitoring. The general state of knowledge of the global rainfall distribution is then discussed. Satellite methods for improving this knowledge are introduced by reference to the available satellites and sensors, the principles and problems of satellite rainfall algorithms, and likely future development of such algorithms. It is concluded that the best global rainfall monitoring scenarios which can be envisaged for the future will involve combinations of data from various sources, including both conventional and new methods of surface rainfall evaluations, plus a growing range of satellites and sensor types.
