Evaluating high resolution climate model predictability and skill in response to the Mount Pinatubo eruption

A central goal of climate research is to determine the perceptible effect of climate change on humans; in other words, the regional and decadal scale effects of carbon dioxide forcing. Identifying the most pronounced and long-lasting responses of climate variables to forcing is important for decadal prediction since forcing terms are one of the sources of predictability on those time scales. Volcanic eruptions provide a powerful, transient forcing on the global climate system by injecting tons of sulfur compounds into the stratosphere that react to form sulfate aerosols. The Community Earth System Model is used to explore predictability in response to the Mount Pinatubo eruption. In this study, the Mount Pinatubo eruption is simulated at very high resolution (T341) using the Community Earth System Model. The predictability of responses to the eruption are calculated and compared with previous studies of the same model at lower resolution for two configurations. All three configurations are compared with observations to evaluate model skill. The Northern Hemisphere winter warming response to the eruption improves in spatial distribution and strength at higher resolution. Stratospheric humidity increases predictably in all model configurations, with spatial analysis showing the that response is centered over the tropical tropopause. The polar night jet response to the eruption is not well replicated for any configuration.