From the website
"Future climate projections from the World Climate Research Programme's (WCRP's) CMIP3 multi-model dataset are statistically downscaled using the CRU CL 2.0 20th century climate dataset."
Narrative from Richard Rood
This is a global data set, produced by the Department of Geography at University of Wisconsin - Madison, The Land Tenure Center, and Conservation International. There is temperature and precipitation for 1975, 2050, and 2090 from three emission scenarios and several CMIP3 models. The downscaling is based on data from the Climate Research Unit as opposed to the Maurer et al. data that have been used for several products in wide-scale usage.