CMIP5 statistical downscaling input

Coupled Model Intercomparison Project Phase 6 (CMIP6) predictors documentation is available here

To develop spatial downscaling, the use of 'predictors' is needed. The 'predictor variables' provide daily information concerning the large-scale state of the atmosphere, while the 'predictand' describes conditions at the site scale (i.e. temperature or precipitation observed at a station).

Large-scale predictor variable information has been prepared for a large North American window. Near-observed data have been derived from the NCEP Reanalysis data set (Kalnay et al., 1996) (for use during the calibration and the validation procedure of the downscaling model), while GCM data for the baseline and climate scenario periods are from the various GCMs experiments. For further information about predictors, their physical links with predictands, including choice/selection and new development, see note on predictors.

SDSM and ASD predictors

Table 1: List of available predictor variables from NCEP and GCM output (i.e. 25 potential candidate atmospheric variables, their origin and time window (i.e. current and future periods).
Predictors (atmospheric variables) Origin (i.e. NCEP or GCM) Time window
Mean Sea Level Pressure
1000hPa Wind Speed
1000hPa Zonal Velocity
1000hPa Meridional Velocity
1000hPa Vorticity
1000hPa Wind Direction
1000hPa Divergence
CanESM2 1961-1990 (baseline climate)
500hPa Wind Speed
500hPa Zonal Velocity
500hPa Meridional Velocity
500hPa Vorticity
500hPa Geopotential
500hPa Wind Direction
500hPa Divergence
CanESM2 1961-1990 (baseline climate)
850hPa Wind Speed
850hPa Zonal Velocity
850hPa Meridional Velocity
850hPa Vorticity
850hPa Geopotential
850hPa Wind Direction
850hPa Divergence
CanESM2 1961-1990 (baseline climate)
Specific Humidity at 500hPa
Specific Humidity at 850hPa
Specific Near Surface Humidity
Mean Temperature at 2m
Total Precipitation
CanESM2 1961-1990 (baseline climate)
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