Precipitation plays a significant role in the climate system, and this book, originally published in 2006, was the first to provide a comprehensive examination of the processes involved in the generation of clouds, rain, snow and hail; how precipitation is measured; how its distribution has changed over time; and how we still need to make improvements to the way precipitation is measured. It traces our attempts to understand what clouds are, from ancient Greeks to the present day. It also discusses developments in the measurement of precipitation, from rain gauges to satellite techniques, and how these measurements have enabled researchers to estimate global trends, totals, variability and extremes of precipitation. This will be a valuable and fascinating reference for academic researchers in the fields of environmental science and climatology. It will also be of great interest to professionals in water resource and flood management.