WorldClim is a set of global climate layers (climate grids) with a spatial resolution of about 1 square kilometer. The data can be used for mapping and spatial modeling in a GIS or with other computer programs.
Robert J. Hijmans, Susan Cameron, and Juan Parra
Museum of Vertebrate Zoology, University of California, Berkeley, Monday, January 1, 2001
Peter Jones, Andrew Jarvis, Karen Richardson