The term geoengineering describes a set of technologies designed to deliberately offset some of the climate effects of anthropogenic CO2 emissions. In this talk, I go through the results of climate model simulations of geoengineering. In particular, I focus on results from the Geoengineering Model Inter-comparison Project (GeoMIP), a worldwide effort to coordinate climate model simulations of geoengineering across multiple models. There are many processes in the climate system that are well represented in climate models, giving us confidence that some of the conclusions one can make about the potential effects of geoengineering, even if those models simulate geoengineering in a highly idealized way, are likely valid. However, there are a substantial number of uncertainties in whether these models can represent more complex processes, such as stratospheric circulation or aerosol microphysical growth that severely limits the knowledge that can be gained from geoengineering simulations. Ultimately, addressing these uncertainties requires model validation using real-world observations; I highlight several potential sources of observations that could be used to test and validate these models.
Speaker Bio: Ben Kravitz is an internationally recognized scientist in climate modeling studies of geoengineering and large perturbations to the climate system. He is the coordinator of the Geoengineering Model Intercomparison Project (GeoMIP), a collaboration between climate modeling centers throughout the world to better understand the expected climate effects of various geoengineering scenarios. Results from GeoMIP have been featured in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, for which Ben served as a contributing author, and the recent National Research Council report on geoengineering. In part for his efforts in advancing this field, he recently received an Early Career Scientist Award from the International Union of Geodesy and Geophysics. In addition to coordinating and participating in GeoMIP, his current activities focus on using engineering techniques in climate models to better understand climate feedbacks, teleconnections, and how the climate responds to change.