Precip, Tmax, Tmin scaled to match CRU monthly data. Global Historical Climatology Network (GHCN), Peterson et al., 1998 NCEP-NCAR Reanalysis Corrected for rain biases (Kalnay et al, 1996; Sheffield et al, 2004) CRU monthly Precip, Temp, DTR 0.5º, Mitchell & Jones, 2005 Spatial disaggregation generally following Sheffield et al., 2006 Temperature disaggregated to 0.25º accounting for elevation TRMM used to disaggregate precipitation to 0.25º Precip, Tmax, Tmin scaled to match CRU monthly data. Gridded 0.25° VIC meteorological data 1

The problem

Few mountain stations in CRU

Solution Develop a set of 12 monthly climatological precipitation maps at 0.25 using DGA data Base historical period (perhaps 1975-2005) Include only stations with relatively complete records (maybe 75% complete and 20 years minimum) Calculate the 12 monthly climatological precipitation values for the 0.25 gridded VIC data set Scale the daily precipitation values in the 0.25 gridded VIC data set so they match long-term (climatological) monthly means.