MIAMI—Heat is a familiar fact of life here. The local NBA team is named for it. The tropical nature of it sets the region apart from the rest of the continental U.S. But that heat is changing.

“You just feel the thickness and heaviness of the air. You can’t even get that relief at 6 o’clock in the morning, and that is different,” said Jane Gilbert, chief heat officer for Miami-Dade County.

The first such public official in the world when she started the job back in May 2021, Gilbert’s goal now is to address what residents here already can feel, that the heat is getting more intense and is more deadly even than other impacts of climate change like hurricanes and rising seas.

This summer is Miami’s hottest yet. During each of the past 14 years the average number of days with a heat index of at least 105 degrees Fahrenheit was six. This year there already have been more than 30 such days, and temperatures do not even peak here until August. By midcentury that number is projected to balloon to 88 days, or roughly three months of the year. Meanwhile water temperatures around the tip of Florida this summer have measured at potentially record-setting triple-digit numbers, prompting coral bleaching and even the death of some corals.

Heat is the leading weather-related killer in the U.S., and most vulnerable are marginalized communities, the elderly, young children, pregnant women and outdoor workers, which is what Gilbert stressed to a small group gathered one recent Saturday morning at a community center in Little River, a low-income neighborhood of Miami not far from Little Haiti.

The neighborhood was one of the most heat-exposed in the county, Gilbert said as she interacted with local residents, who found some relief from the heat inside the center.

Gilbert gave a presentation on heat and climate change and was joined by local nonprofit leaders, an academic heat expert and representatives from other agencies and organizations like Miami-Dade’s Emergency Management Department. Residents asked questions, were treated to a lunch of traditional Haitian food and went home with “cooling kits,” which included battery-powered fans and packets of electrolyte capsules. In a sense, Gilbert aims to reinvent the concept of heat here, where it often is taken for granted.

“It’s underappreciated, the risks,” she said.

Beyond the community center, mobile homes baked in the sun, most of them cooled only by window units. In front of some houses, their occupants sat on porches—running their air conditioners made their utility bills unaffordable. In that, they joined those similarly situated in a global cohort of hot spots where officials have also seen fit to hire chief heat officers like Gilbert—Phoenix and Los Angeles, here in the U.S., plus Bangladesh and Sierra Leone; Athens, Greece; Melbourne, Australia and Santiago, Chile. 

Three Main Goals

Heat is responsible for an estimated economic impact in Miami-Dade County of some $10 billion annually, a cost that is projected to double by midcentury. The number is based on lost worker productivity alone and does not consider other factors like tourism. Miami-Dade is the most populous county in Florida with some 2.7 million residents.

Before Gilbert was the county’s first chief heat officer she was the city’s first chief resilience officer. Eventually she left that position and began doing consulting work for the county, including a series of community meetings in vulnerable neighborhoods aimed at teasing out local concerns about climate change.

“It was not sea level rise. It was not hurricanes. It was extreme heat,” she said.

After she became chief heat officer, Gilbert assembled a Climate and Heat Health Task Force to examine local needs and develop recommendations. She also commissioned a couple of vulnerability studies. One was aimed at identifying zip codes with the greatest concentrations of emergency room visits and hospitalizations related to heat, and the demographics of those areas. The other study looked at heat mortality.

The research showed that while Miami was getting hotter, certain residents were more affected. Most notably some zip codes were found to have more than four times the number of emergency room visits and hospitalizations related to heat compared with others, and among the biggest risk factors were high poverty rates and high percentages of outdoor workers and families with children. 

The research also showed there was a clear correlation between heat mortality and the heat index, which is a measure of how the body feels when the air temperature is combined with relative humidity. Interestingly, the studies found that most of the deaths occurred at heat indexes below those used by the National Weather Service as the basis for advisories and warnings.

Armed with these findings, the task force held another series of public workshops to establish priorities, and Gilbert organized the priorities under three main goals. One of them was to enhance local communication by, for instance, lowering the thresholds for heat advisories and warnings. The goals also were aimed at improving health care, helping residents keep their homes cool, providing more cooling sites like libraries and reducing heat by, for instance, expanding urban tree canopies.

“We’re getting hotter not only because of climate change but also because of how we’re developing as cities,” Gilbert said.

This summer the National Weather Service issued its first-ever Excessive Heat Warning for Miami-Dade County, on July 16. The heat index that day at Miami International Airport was 110 degrees Fahrenheit. There have been three more Excessive Heat Warnings since then. 

Meanwhile, last summer Mayor Daniella Levine Cava declared the county’s first-ever heat season, modeled after hurricane season and aimed at raising awareness that residents should take precautions. The heat season begins May 1 and ends Oct. 31. 

For the past three years, local legislative leaders have joined with agricultural workers to push for a statewide heat standard, to protect outdoors workers. The proposal never advanced in the Legislature, and now the county is working toward an ordinance to protect construction and agricultural workers.

“Just the fact that we have the heat season is a huge change,” said Olivia Collins, senior director of programs at the CLEO Institute, a nonprofit dedicated to climate education and advocacy. Collins was at the event at the community center.  

Tiffany Troxler, associate professor at Florida International University’s Department of Earth and Environment, described Gilbert’s work as forward-thinking.

“Those advisories and warnings are established based on trying to minimize deaths related to heat, and if those heat thresholds are set too high then people will die,” said Troxler, who also was at the community center event.

Before Gilbert’s appointment as chief heat officer, it was not well-understood how heat affected Miami-Dade County and its citizens, Troxler said.  

“She’s incredibly dedicated to trying to identify the suite of measures that are necessary to protect our most vulnerable communities, and she strongly leverages science to do that,” Troxler said. “The fact that she was able to get organized in advance of this extreme heat season that we’re encountering right now, and work with the National Weather Service to pilot the lowering of the heat thresholds that trigger our heat advisories and heat warnings, I mean, thank God.”

Added Lynée Turek-Hankins, a doctoral candidate studying climate adaptation at the University of Miami’s Rosentiel School of Marine, Atmospheric and Earth Science: “I feel safer knowing that she is working on this issue.”

Turek-Hankins was part of the Climate and Heat Health Task Force. “She really does care about people and making sure that their quality of life is improved,” she said of Miami’s CHO.

Ground-Breaking

At the community center, Gilbert stood before the gathered residents, who were seated around small circular tables. She is tall and lean with shoulder-length gray hair, and she wore shorts and a county-issued polo shirt. Larger folding tables lined the walls where residents could gather fliers and information from the other agencies and organizations present. Gilbert gave a PowerPoint presentation that included ways the residents could protect themselves from the heat.

“If you can’t afford (air conditioning) at home or it’s not working or you don’t have it there are strategies to stay cool,” she said, “like a shower and cooling towels. You can wet them and put them around your neck and head.”

Afterward, Gladys Penn said she has noticed a change in the heat since she moved to Miami in 1958. Now a retired postal worker, Penn said she has restructured her time so that she can get errands done in the morning, before the hottest time of day. She also makes a point of drinking lots of water, because otherwise she gets cramps in her legs.  

“When it gets hot I just don’t go out anymore,” she said.

Londa Kee found the heat most bothersome during her commute to work at a local McDonald’s restaurant. She takes a bus.

“For me to go to work I just try to make sure I drink some liquids before I leave,” she said. “That heat is no joke.”

These are the residents Gilbert is most concerned about as she leads a world-class city to a deeper understanding of a surging global killer. 

Collins described the chief heat officer’s work as ground-breaking.

“It’s sending a message,” Collins said, “to the rest of the world, and I think more and more of this kind of position will become more common. But I think it’s a good first step.”