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San Francisco Bay Area Precipitation in a Warmer World

With climate change, it’s important to better understand the frequency and strength of precipitation events and how they may affect inland flooding. San Francisco undertook a unique collaboration between a municipality, climate scientists at Lawrence Berkeley National Laboratory, and climate consultants at Pathways Climate Institute to create a research team that focused on a better understanding of future precipitation events through climate modeling. Using supercomputing resources at LBNL’s National Energy Research Scientific Computing Center, the research team found that the effect of climate change on future storms is predicted to be significant, leading to more powerful events unleashing substantially more water.

This initially resulted in a report published in April 2022. This two-volume report provides groundbreaking scientific data on precipitation events for use by the entire City as we develop planning tools and policies to adapt to a changing climate with increasingly extreme storms. These two volumes highlight that both large and small storms are increasing in intensity.

Volume 1: State of the Science

Volume 2: Future Precipitation Intensity, Duration, and Frequency