I'll give an overview of recent work on how radiative feedbacks depend on the spatial pattern of sea-surface temperature (SST) - the so-called 'pattern effect' - and how this dependence confounds our estimates of equilibrium climate sensitivity (ECS) from both instrumental and proxy records. New modeling and observational analyses, such as the use of localized warming patch simulations and the use of satellite observations, provide clarity on the key regions and mechanisms linking radiative feedbacks to SST patterns. New analyses using CMIP5 and CMIP6 models quantify how radiative feedbacks will change as warming patterns evolve in the future, but large uncertainty remains, implying that the historical record currently provides limited information about the upper bound of ECS. It has been suggested that the paleoclimate proxy record may thus provide our strongest constraints on ECS, but the role of SST patterns in the radiative feedbacks estimated from past climate states has not yet been accounted for. I will describe preliminary work to estimate the importance of the pattern effect in the context of the Last Glacial Maximum and the Pliocene.
GFDL Formal Seminar
Thu, Jan 23, 2020, 2:00 pm to 3:00 pm
Smagorinsky Seminar Room