Do CMIP5 simulations of Indian summer monsoon rainfall differ from those of CMIP3?

To understand the improvements in the simulations of Indian summer monsoon rainfall (ISMR) by Coupled Model Intercomparison Project 5 (CMIP5) over CMIP3, a comparative study is performed with the original and statistically downscaled outputs of five General Circulation Models (GCMs). We observe that multi‐model average of original CMIP5 simulations do not show visible improvements in bias, over CMIP3. We also observe that CMIP5 original simulations have more multi‐model uncertainty than those of CMIP3. The statistically downscaled simulations show similar results in terms of bias; however, the uncertainty in CMIP5 downscaled rainfall projections is lower than that of CMIP3.