Urban Heat and Wildfires in Southern California

How can we better leverage existing research and platforms to refine and meet extreme heat adaptation targets?

So far this year, at least six daily heat records were broken in Central and Southern California on Wednesday, including the hottest-ever Sept. 30 at Los Angeles International Airport (92 degrees) and Long Beach Airport (105). At the same time, eight of the 10 largest fires in California history have burned in the past decade and, this year, the August Complexfire  became the largest fire in the state's history, burning a total of 1,032,648 acres or, about 1% of California's land, an area larger than the state of Rhode Island. These hazards go hand in hand with intensifying risk to public health, homes and displacement, energy availability, and economic disruption.  The most vulnerable include seniors, communities of color, and outdoor laborers continue to be disproportionately impacted and bear the burden of the legacy of environmental injustice. 

In 2019, CRCL supported the design and facilitation of the SCRI Wildfire Resilience Workshop in partnership with The Conrad N. Hilton Foundation and Resilient Cities Catalyst and with partners from Ventura County, LA County, TreePeople, and Climate Resolve. The workshopped surfaced ideas to pilot the world’s most innovative solutions to fire and urban heat in the Los Angeles region. SCRI aims to strengthen the region’s preparedness for wildfire and extreme heat as well as other climate threats. And because the impacts of wildfires and other climate threats are not confined to municipal boundaries, SCRI is working to foster coordination at the regional scale. 

As a part of this effort, CRCL partnered with LA County to prepare “Heat Vulnerability in Los Angeles County Resource and Methodology Assessment.” In support research and planning that advances resilience and climate adaptation planning around extreme heat. In the development of the County’s OurCounty Sustainability Plan, the County established ambitious targets around converting heat trapping surfaces to cool or green surface, reducing the number of heat stress emergency department visits, and increasing the urban tree canopy cover. In addition, the County is pursuing a holistic climate vulnerability assessment. In service of these efforts, the Center for Resilient Cities and Landscapes assessed existing climate studies in the region and global best practices in order to inform the methodology used by the County in their broader climate adaptation planning effort.  

CRCL looked across nine studies and tools that define and illustrate heat vulnerability in Los Angeles and Southern California - from State-wide climate projections prepared as a part of the Fourth Climate Assessment and Cal Adapt platform to visualization and mapping tools like the California Healthy Places Index and the California Heat Assessment Tool. Then, we evaluated them for their limitations and strengths in view of the targets set by the County in the OurCounty plan. CRCL also prepared case studies of global best practices in defining and studying heat vulnerability and prepared recommendations for the methodologies that the County might pursue in confirming, refining, and meeting the targets and actions identified in their planning efforts.




Grga Basic

Johanna Lovecchio



Los Angeles County

Conrad N. Hilton Foundation

Resilient Cities Catalyst