Using Large Ensembles to Identify Regions of Systematic Biases in Moderate‐to‐Heavy Daily Precipitation

Abstract

AbstractBecause of internal variability in both the real‐world and global climate models, it is unclear whether disagreement between models and observations reflects true systematic differences, or different phasing of internal variability in the short observational period. Here, we address this issue through an examination of moderate‐to‐heavy precipitation in large ensembles of global climate models. We find that model inconsistency with a global observational product is lowest for extratropical precipitation in northern hemisphere winter. The inconsistency is systematically greater for the southern hemisphere winter, but the difference between hemispheres could be due to observational quality. Moderate‐to‐heavy extratropical winter precipitation is less inconsistent than moderate‐to‐heavy tropical precipitation in most models. Within the tropics, moderate‐to‐heavy precipitation is particularly inconsistent with the reference in regions including the Caribbean (especially during JJA), the northern and southern flanks of the Pacific and Atlantic ITCZ, and the Indian Ocean.