As extreme heat — the worst U.S. weather-related killer — worsens nationwide, the country’s three new Chief Heat Officers shared at a Sept. 29 briefing the lessons they learned about how the threat to their cities is changing their efforts to protect urban residents.
Los Angeles
Marta Segura, Chief Heat Officer (CHO) of Los Angeles, Calif. since June 2022, said that summers in her city are intensifying and lengthening into “heat seasons” which, now run from mid-June to mid-November.
While Southern California — where an average hot day is just under 94 degrees Fahrenheit — currently experiences seven days a year which exceed this average, that number is projected to reach 21 days by 2053.
The summer before this one was the “hottest heat season on record for Los Angeles. We had 10 straight days of an extraordinary heatwave,” she noted — views of how to mitigate this heat are becoming more holistic, involving a collaboration of departments including public health, decarbonization, urban forestation, emergency response, and housing.
To prepare for future heat seasons, for example, LA is decarbonizing its transportation and energy infrastructure, as well as from buildings including cooling centers, which have been the most crucial tool for heat help.
Noting that the process of protecting people from worsening heat is inseparable from the process of addressing what worsens this heat, Segura added that the city aims to eliminate greenhouse gas emissions from all buildings by 2050.
Heat-related illnesses and deaths disproportionately affect communities of color living in low-income, historically redlined neighborhoods, often in houses with no air conditioning. Key to mitigating the impacts of extreme heat on these vulnerable populations, said Segura, is planting trees to cool these “historically underinvested communities.”
She pointed to the Heat Ready CA campaign, launched last July, as a statewide example of her aim to “align extreme heat and climate goals with equity and health goals,” by focusing outreach about extreme heat upon those most vulnerable to it. LA launched a similar seven-language Heat Relief 4 LA social media campaign last May, and will release a heat resilience action plan in March 2024.
Miami
Jane Gilbert, who has served as CHO for Miami-Dade County, Fla. since June 2021, agreed that intensifying heat seasons are creating a need for community heat action which is coordinated across governments: “It’s not just one department that can solve this problem. Extreme heat requires emergency response, communications, urban planning, tree planting, and housing. If you want to go fast, go alone, but if you want to go far and have a great impact, you need to go together.”
Working to achieve both heat and energy resilience with local departments, for example, her office recently installed 1,700 efficient AC units in public housing across the county’s 34 municipalities — fortunately “before this summer, because it was really challenging. While we have an average of about seven days out of the year above the heat index of 105 in the last 15 years … This year we had over 50 days with a heat index over 105.”
Gilbert noted that heat-related hospitalization varies drastically across Miami-Dade County’s population of 2.6 million people, as “some zip codes have four or five times the number of heat related emergency department visits and hospitalizations than other zip codes. The strongest correlating factors are high poverty rates and high land surface temperatures — in other words, urban heat islands … more asphalt, less trees.”
While 20% of the county has tree canopy coverage, she aims to raise this to 30% by 2030 through collaboration with community-based urban forestation organizations.
Given that most crucial to heat outreach is a focus upon the areas and demographics most vulnerable to heat, Gilbert added that community-based organizations are also key to placing information about extreme heat — in English, Spanish and Haitian Creole — on social media, traditional news media, the radio, and on bus shelter ads, and in-person at the organizations themselves.
Phoenix
David Hondula, CHO of Phoenix, Ariz. since October 2021, said that, as responses to heat become more comprehensive, involving a collaboration across communities and local government departments, the barrier to this collaboration becomes one of communication.
He noted, as an example of this barrier, the initial absence of non-bilingual information about urban forestation efforts in Phoenix: “When a community organization wants to do business with the city government to put more money into forestation but not all of our information is available in English and Spanish, it’s a lot harder to engage the community in tree planting. We’re hopeful that our efforts to make every step bilingual will spill over into the rest of our work in Phoenix.”
The need for more comprehensive heat outreach was especially crucial this summer, which Hondula said “set a new record for the number of 110 degree days in July … after a relatively mild June,” July made history as the hottest month ever recorded in a U.S. city. Every day in it but one topped 110 degrees.
By September, Phoenix had topped its overall record with 54 days reaching 110 degrees, above its 2020 record of 53 days. Consequently, “firefighters responded to about twice as many heat-related 911 calls that month compared to years past, and we’re tracking about 25% more heat-related deaths confirmed than last year.”
The population most vulnerable to heat-related illness and death in Phoenix are the unhoused. “Here, the heat challenge and homelessness challenge are really one and the same,” he said. “Some years, 40%, 50% of our heat-associated deaths occur among people experiencing homelessness.”
The most effective outreach on this front has been word-of-mouth, and the more it succeeds, he continued, the most it raises the question of “What it means to have accessible cooling centers” for those who may not be able to leave their belongings to access them?
Despite the political divisiveness of climate change on the national scale, the immediate threat of heat spurs on action at the community scale, Hondula said: “I don’t have a strong sense that the broader climate politics have really interfered with our mission. I don’t think there’s a strong public objection here to the idea that people are suffering in the heat.”
“Even the reddest hats that we encounter will talk about how much cooler the city used to be,” he added. “They’ll talk about playing in bare feet when they were children here … They feel like the environment here has changed so much that the urban climate story does not seem to be as politically charged as the global climate story.”
