The downscaled global climate model simulations (CMIP3) were developed by The Nature Conservancy for The World Bank. The background and methods are described by Girvetz et al. (2013), with added details in Thrasher et al. (2012). This website allows you to download CMIP3 data in SWAT file format for a given location and time period.
As unconstrained coupled models, the climate simulations do not ingest observed sea surface temperatures, precipitation, or other weather or land surface observations. Thus, there is no expected correspondence on a year-to-year basis of historic simulated climate and observed weather. In addition, because of the bias correction involved in the downscaling, climate model skill (based on these downscaled data) in reproducing historic observations is not meaningful for ranking GCM performance (Maurer et al., 2014).