The scientific study of climate. Climate is the expected mean and variability of the weather conditions for a particular location, season, and time of day. The climate is often described in terms of the mean values of meteorological variables such as temperature, precipitation, wind, humidity, and cloud cover. A complete description also includes the variability of these quantities, and their extreme values. The climate of a region often has regular seasonal and diurnal variations, with the climate for January being very different from that for July at most locations. Climate also exhibits significant year-to-year variability and longer-term changes on both a regional and global basis.

The goals of climatology are to provide a comprehensive description of the Earth's  climate over the range of geographic scales, to understand its features in terms of fundamental physical principles, and to develop models of the Earth's  climate for sensitivity studies and for the prediction of future changes that may result from natural and human causes. Climate history Climate modeling Climate modification Weather