Sweaty season is here. Daytime temperatures in the sauna we call South Florida will soon settle into the high 80s and weather experts are forecasting a hotter than normal summer. Again.
“Last year was the warmest since 2010 in South Florida, and seven of the past 10 summers have been above normal,” said National Oceanic and Atmospheric Administration meteorologist Stephen Baxter. “With your spring dry conditions and sea surface temperatures that continue to run substantially higher than usual you’re looking at another warming trend.”
So expect seven months of scorching, sapping, sometimes life-endangering weather. What to do, beyond moving to northern locales that are also getting warmer? Some cities are developing strategies to beat the heat as they confront this growing threat to the health of urban populations.
Phoenix is a leader. In the desert city where temperatures are already hitting 105 degrees and typically spike to 110-115, the second year of the “We’re Cool” campaign is under way. Residents can take a break in designated air-conditioned respite sites at churches, Salvation Army shelters, homeless shelters, community centers, senior centers, libraries, fire stations and municipal buildings, where they can also get wellness checks and information on preventing and treating heat-related illnesses. There are free water stations arrayed around the metro area, part of Maricopa County’s Heat Relief Network, which is advertised on trains and buses.
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“Arizona has dry heat – different from Miami but just as harsh,” said Michael Hammett, chief service officer in the city manager’s office. “We’re particularly concerned about low-income people and people with health risks. We don’t want them to get sick or wind up in the hospital. We want them to know about places that may be right around the corner or along their commute where they can find hydration and relief.”
Cities such as Seattle, Toronto, Cincinnati, St. Louis and Philadelphia also open a network of shelters during heat waves. Volunteers knock on the doors of elderly residents to check on them.
“Heat is the greatest weather-related killer in the U.S. – greater than tornados or hurricanes,” said Dr. Laurence Kalkstein, climatology professor at the University of Miami’s Miller School of Medicine in the department of Public Health Sciences. “It’s a sneaky killer, a silent killer. There is poor public awareness of heat. People go about their day figuring they’re immune to it. But we’ve got a huge vulnerable population of aging people who don’t sweat as efficiently, obese people, people on medication, homeless people.”
At least 35,000 people died in Europe during the record-breaking heat wave of 2003. Yet Miami, with its subtropical heat and humidity, is not as vulnerable to heat-related health problems as Paris and London, or even New York.
“Our weather is the same day after day, 88-90 degrees with 80 percent humidity,” Kalkstein said. “People are used to this pattern for seven months every year. It’s not variable and it’s not searingly hot. We’re saturated by air conditioning and most homes are amenable to heat.
“It is getting warmer, but I believe humans will adapt. Five feet of water might make Miami uninhabitable eventually, but not the heat.”
South Florida’s average temperature is forecast to be 82.5 degrees through August, NOAA’s Baxter said. That is four tenths of a degree above normal, “which sounds subtle but is actually quite significant,” he said.
Florida’s average temperature from January through April was the warmest year-to-date on record, NOAA data shows.
Aside from reducing the body temperature of citizens, cities are looking for ways to reduce the temperature of the urban core. Innovative solutions include roof materials and paint that reflect heat, reflective pavement and asphalt, green roofs. More trees mean more shade. The Global Cool Cities Alliance and the American Council for an Energy Efficient Economy surveyed 26 North American cities and found they are “confronting the challenges of extreme weather, adapting to a changing climate and improving the health and resiliency of urban populations.”
Kalkstein is planning an experiment at UM; he’ll install window film from the 3M company on a building to find out how much the interior can be cooled.
He’s also principal investigator on a study on how to cool Los Angeles, in collaboration with UCLA, 3M, the Tree People and the U.S. Forest Service.
“This transcends any controversy over climate change,” he said. “If we can cool a city by three degrees it makes a big difference in the lives of its people.”
In 2016, the average temperature in the contiguous U.S. was above the 20th century average for the 20th consecutive year, and 2.9 degrees above that average, according to NOAA. The year-to-date average temperature for the U.S. through April was 4.5 degrees above average.