Influence of cumulus parametrizations on the performance skill of seasonal rainfall analysis
Sensitivity of the regional climate model RegCM4 to cumulus convection schemes were assessed for the 2015/16 El Ni˜no over the Philippine region. The European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis Interim (ERA-Interim) reanalysis was used as boundary conditions to RegCM4 in simulating rainfall from June 2015 to May 2016 at 25 km horizontal resolution. Rainfall was compared with satellite measurements of the Tropical Rainfall Measuring Mission (TRMM) and reanalysis data from ERA-Interim with horizontal resolutions of 0.25° and 0.75° respectively. Downscaled rainfall performed better with respect to TRMM depending on the season and choice of cumulus parametrization. Initial findings showed that the Tiedtke cumulus scheme over land andocean performed the best overall especially during the northeast monsoon period. Changing the region, land surface model, and reanalysis dataset may favor a different scheme.