CAREER: Aerosols as Drivers of Multivariate Climate Hazard

About This Grant

This project examines aerosol impacts on multivariate climate hazards that have great significance to society, including the concurrent extreme events of fire weather, humid-heat, and drought events. Aerosols have a larger impact on univariate extreme temperature and moisture events per unit global mean temperature change than greenhouse gases. However, their role in multivariate climate hazards is unknown and a framework on how to consider aerosols when attributing and planning for these hazards is also lacking. At the same time, aerosols are increasing because of increases in both anthropogenic and natural sources, accelerating the need to understand their role in climate hazards. This study addresses this need by 1) developing methodologies to uncover the influence of aerosols on multivariate climate extremes using state-of-the-art climate models; and 2) educating the next generation climate workforce with greater awareness of the factors contributing to multivariate climate extremes and the tools to enable robust societal planning for climate risk, taking into account these impacts. A key hypothesis of this work is that aerosols can have a greater impact than greenhouse gases on temperature and moisture and, thus, multivariate climate hazards in certain regions and for specific events. The project will examine this hypothesis using existing and emerging model output from the multi-model single forcing large ensemble (SFLE) aerosol intercomparison project and the Regional Aerosol Model Intercomparison Project (RAMIP). The SFLEs provide a decomposition for all pre-industrial through present day forcings into greenhouse gas-only forcing and anthropogenetic aerosol-only forcing, while one member additionally provides biomass burning (“black carbon”) aerosol-only forcing. The RAMIP, and a new black carbon-only forcing ensemble generated by this work, looks at how uncertainties associated with total aerosol emission, regional emission, and individual aerosol species impact near-term climate change. The project also develops novel aerosol-aware event attribution methodologies to better represent the impacts of aerosols on multivariate climate hazards both historically and in the future. To meet a growing need for a workforce trained in the computational and scientific theories specific to climate at the undergraduate level, this project integrates an undergraduate immersive, earth system modeling “field trip” framework and experiential earth system modeling curriculum for climate system science undergraduates with the goal of building the quantitatively climate-literate workforce needed to allow cross-sectoral operational climate planning. Finally, the project will mentor a doctoral student in aerosol processes and their role in multivariate climate extremes, climate hazard attribution methodologies, and undergraduate educational curriculum development. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.