Seasonal extrema of sea surface temperature in CMIP6 models

Abstract. CMIP6 model sea surface temperature (SST) seasonal extrema averaged over 1981–2010 are assessed against the World Ocean Atlas (WOA18) observational climatology. We propose a mask to identify and exclude regions of large differences between three commonly used climatologies (WOA18, WOCE-Argo Global Hydrographic climatology (WAGHC) Hadley Centre Sea Ice Surface Temperature data set (HadISST)). The biases in SST largely consistent with annual mean biases. However, amplitude spatial pattern bias vary seasonally 20 models assessed. Large variations occur eastern boundary upwelling regions, polar North Pacific equatorial Atlantic. These results demonstrate importance evaluating performance not simply properties. Models greater vertical resolution their ocean component typically better representation extrema, particularly maximum SST. No significant relationship horizontal is found.