Where in San Diego County do children face the most heat stress? Where is nighttime heat most dangerous? Or where would people benefit most from new shade infrastructure?
A new tool researchers at the San Diego Regional Climate Collaborative and Scripps Institution of Oceanography’s Center for Climate Change Impacts and Adaptation unveiled Wednesday can answer those and other questions about where it’s hot in the county, who is most at risk and why.
The San Diego Heat Risk Explorer uses open-source data such as Census tracts, weather observations, chronic disease prevalence, land surface temperature, social conditions like income and housing, and the commonness of air conditioning.
Researchers said all of this information about San Diego County has long been available, but not all in one place.
Similar tools evaluating extreme heat, such as the state’s Cal-Adapt website and the city of San Diego’s Urban Heat Vulnerability Index, have also existed. But they either have “static data,” lack “layers of different socioeconomic vulnerability,” or are limited to just one jurisdiction, said Darbi Berry, director of the Collaborative.
Users of the San Diego map have three main topics, or pillars, to select from to learn more about how heat impacts a neighborhood and how it compares to other parts of the county. Variables include daytime or nighttime heat, health conditions like asthma, sociodemographics such as seniors living alone or people experiencing food insecurity, and those living in neighborhoods with an abundance of shade created by trees. It also includes tribal lands, cool zones and what conditions could look like in the years 2050 and 2080.
The map can reveal how neighborhoods can experience similarly hot temperatures but have very different health outcomes. For example, residents in one neighborhood may cope better because they have air-conditioned homes and live near cooling centers. While others may have more elderly residents living with fewer shady green spaces and other areas to cool down.
“When it's hot, you know, you either have to make some decisions around how to cool your home, understanding our energy costs are, you know, ever increasing, or some people have to make decisions on where to go,” said Berry.
The data can also inform how people cope with heat waves depending on where they live, she added. For example, she said, people in coastal communities who may not have air conditioning.
“Even though it’s cooler … we’re seeing in the coastal communities that people’s bodies are actually acclimated to not withstand those heat waves,” she said. “So, it’s also having this understanding that these communities might now show up as having a ton of daytime heat days, but their AC levels are really low. So, when a heat wave does hit, those community members are really vulnerable.”
Researchers said the map can help city leaders make decisions about solutions and inform residents about their neighborhoods’ needs to better withstand extreme heat.
“It’s like democratizing data,” said Connor Mack, one of the researchers at Scripps. “If that is used at a really local level, I think it can be really powerful, giving people information.”
Mack said solutions could include knowing where to plant more trees, adding sealant to pavement to keep it cooler and improving access to more air-conditioned spaces.
The Explorer map was developed with grant funding from the state’s Extreme Heat and Community Resilience Program.
As part of the grant program, Berry said step one was to develop the map and then work with cities to develop heat action plans and a cooling solutions tool kit.
