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California Heat Assessment Tool Selected for the Project Merit: Climate Change Adaptation and Resilience Award

February 27, 2019

Image: Screenshot of the CHAT toolThe California Heat Assessment Tool (CHAT) has been selected by the Climate Change Business Journal for a Project Merit: Climate Change Adaptation and Resilience award, for its innovative approach to helping public health officials, health professionals and residents understand what changing heat wave conditions mean for them, through a free online platform.

CHAT is part of California’s Fourth Climate Change Assessment, a state-mandated research program to assess climate change impacts in California, and was developed by Four Twenty Seven, Argos Analytics, the Public Health Institute and Habitat 7 with technical support from the California Department of Public Health.

Explore the interactive tool.

As California’s climate warms, residents increasingly endure extreme heat events. This exacerbates existing risks and will bring new challenges for different regions, threatening the efficacy of traditional intervention strategies. Current thresholds for heat alerts are based on temperatures that exceed historical statistical thresholds rather than temperatures that impact public health. These “health-neutral” thresholds may underestimate health risks for the most sensitive populations.

CHAT is an interactive online tool that informs adaptation for extreme heat and helps planners and public health practitioners prioritize actions. Users can explore population-specific projections for several characteristics of extreme heat events over the coming century alongside demographic information across California, providing both a snapshot of statewide trends and granular information for each census tract. 

CHAT helps identify neighborhoods with populations vulnerable to heat and overlays projections for heat events likely to cause health impacts. This new research establishes local, health-based thresholds for extreme heat that help public officials, health professionals and residents understand what changing conditions mean for them. The tool can be searched by city, county or zip code and provides data at the census tract level.

Additional Resources on climate change and health