What is a downscaling predictor?
To develop spatial downscaling, the use of daily predictors is needed. The predictor variables (e.g. mean temperature at 2m, mean sea level pressure, 500 hPa geopotential height, etc.) provide daily information concerning the large-scale state of the atmosphere, while the predictand describes conditions at the site scale (e.g. temperature or precipitation observed at a station). The observed large-scale predictors have been derived from the NCEP Reanalysis data set (for use during calibration and validation of the downscaling model), while GCM data for the baseline and climate scenario periods have been derived from GCM experiments (presently CGCM1, CGCM2 and HadCM3). For more information about predictors, please see Reports and Publications and Note on Predictors.
