Purely adding this link here as a potential resource for future:
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.
http://www.worldclim.org/Another site:
The data distributed here are in ARC GRID, and ARC ASCII format, in decimal degrees and datum WGS84.
http://www.ccafs-climate.org/
