Surface precipitation rates are simulated 'reasonably well'. However, the model tends to overestimate the observed precipitation, in all runs. Having discussed the above results, we have the following comments about the procedures for Case 3. The Runs to be specified should address particular scientific or SCM technical issues. No scientific issues have been advanced for Case 3.
Possible issues fall into different subjects, such as, clouds, radiation, and cumulus convection.
For different subjects, those who are interested in analyzing results from the SCM Intercomparison can discuss what is the best way to run the model so that we can get what we want from the Intercomparison results. For example, separating the whole IOP into several small pieces based on different weather conditions could be one way to go for testing cumulus convection schemes. Nudging temperature and moisture back toward their observed values could be useful for testing cloud schemes. With regard to radiation, Steve Krueger has suggested a run where the radiation is specified, so that we control for different radiation schemes in the participating SCMs. Finally, some runs need to be designed for identifying sources of errors, i.e., to identify whether errors are from large-scale forcing or from model parameterizations.