Report 22:    The Effect of Horizontal Resolution on Cloud Radiative Forcing in the ECMWF Model

Potter, Gerald L.
May 1995, 28 pp. 

The ECMWF general circulation model (cycle 33) was used to test the effect of horizontal resolution on the simulated cloud radiative forcing. The model was run with four resolutions: T21, T42, T63 and T106 and the results were compared to the Earth Radiation Budget Experiment (ERBE). The ECMWF model produces relatively large errors in comparison to observations for January and July which can be attributed to the model being too dry and clouds too reflective. Only the T21 resolution displays substantial differences from the other resolutions, and all resolutions are substantially different from ERBE observations. (pdf file)