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An evaluation of surface radiation budget over North America in a suite of
regional climate models
M. Markovic 1 , C. G. Jones 1 , P. Vaillancourt 2 , K. Winger 1 , D. Paquin 3
1 Department of Earth and Atmospheric Sciences, UQAM, 550 Sherbrooke West, 19 th floor, West Tower, Montreal H3A 1B9,
Canada, 2 Numerical Forecast Research Branch, Environnment Canada, 3 Consortium Ouranos, Montreal, Canada
e-mail: markovic@sca.uqam.ca
In this study we evaluate the components of the surface
radiation budget (SRB) (downwelling longwave, DLR and
incoming shortwave radiation, ISR) in three regional climate
models (RCMs): CRCM (The Canadian Regional Climate
Model), GEM-LAM (Regional version of Global
Environmental Multiscale Model) and RCA3 (Regional
model of Rossby Centre, Sweden) against surface
observations. All three RCMs use different radiation and
cloud schemes, characterizing systematic errors in the SRB
as a function of climatic conditions will aid in model
improvement.
The RCMs will be directly compared with available surfacebased
measurements (SURFRAD Network) over different
conditions. We will determine the quality of the simulated
radiation budget in the respective models and target the
areas and climatic conditions where the models give the
worst results. By evaluating the surface radiation budget in a
variety of climate conditions, for cloudy and clear conditions
separately and as function of season and time of day, we aim
to isolate conditions and situations where the respective
cloud and radiation schemes operate poorly and identify
aspects of the parameterization schemes that are causing
these simulation errors.
While surface based radiation observations offer accuracy at
high temporal resolution, they do not allow full evaluation
of the simulated SRB and cloud cover across the entire
North America. In order to compare the RCMs over wider
geographical domain we first evaluate ISR, DLR and cloud
cover for various possible observational surrogate datasets:
ERA40 (ECMWF Reanalysis), NARR (North American
Regional Reanalysis, NCEP) and ISCCP (International
Satellite Cloud Climatology Project).