Assessment of Precipitation in CMIP5 Models Using TRMM Data

General Circulation Models (GCMs) often have difficulty accurately predicting annual rainfall rates in the tropics, specifically when detailing the difference between convective and stratiform precipitation. Five of the Coupled Model Intercomparison Project 5 (CMIP5) models were selected and their corresponding parameterizations for stratiform and convective precipitation were recorded. Parameterizations for both convective and sratiform precipitation describe how the models formulate these processes and can ultimately reveal why the different precipitation types are often forecasted inaccurately. The five chosen CMIP5 models, with data ranging from 1990-2005, were read in, averaged annually for the given years, and plotted in units of mm/day. The data was then looked at in plots of annual total, convective, and stratiform precipitation, stratiform rain fraction, and seasonal averages of all three types of precipitation. Data output from the Tropical Rainfall Measuring Mission (TRMM) satellite was manipulated similarly. Comparing the model data to the observed satellite data will reveal if the five chosen CMIP5 models accurately represent the types of precipitation in the tropics. Preliminary results show that the models are inaccurately predicting stratiform precipitation primarily in the middle latitudes and underestimating stratiform precipitation in the tropics.