Jun 8, 2022 - Energy & Environment

Heat waves could soon have names

Illustration of a smoldering name tag sticker with burn holes
Illustration: Natalie Peeples/Axios

There's a growing effort to name and categorize heat waves the way we do hurricanes — to call attention to their significance, alert people to dangerous temperatures and prod public officials into action.

Why it matters: Heat waves are the deadliest type of weather emergency in the U.S. They're bigger killers than floods, tornadoes or hurricanes — and they're growing in frequency and intensity due to global warming.

  • Excessive heat — which hits low-income communities the hardest — doesn't lend itself to dramatic TV coverage, so people sometimes underestimate the risk.
  • Proponents of a more formal public warning system say it could save lives and trigger measures like opening community cooling stations and asking people to stay indoors.

Driving the news: This month Seville, Spain is poised to become the first city to start naming severe heat waves.

  • Five other cities — Los Angeles; Miami; Milwaukee; Kansas City, Missouri; and Athens — have also started piloting a similar initiative, using weather data and public health criteria to categorize heat waves.
  • They'll use a three-category system that organizers want to standardize. Each city's system will be tailored to its particular climate.
  • A "category three" heat wave in L.A., for example, will look and feel quite different from the same designation in Milwaukee.

"Some of the places least accustomed to heat are the most at risk," says Kathy Baughman McLeod, director of the Adrienne Arsht-Rockefeller Foundation Resilience Center (known colloquially as Arsht-Rock), which is spearheading efforts to name and categorize heat waves.

Details: Under the warning system starting up in the six global cities, "category one" is the least severe, while "category three" would be "the top 10% of terrible heat waves," said Larry Kalkstein, Arsht-Rock's chief heat science adviser.

  • "For all three of them, we’d recommend to stay indoors in air conditioning as much as possible," he tells Axios.
  • Each participating city "has a different set of formulas" that will determine what the categories look like, based in part on their urban structure, Kalkstein said. For example: Philadelphia has lots of brick row homes with black tar roofs that trap heat.
  • Any of the designations would ideally prompt city pools to open, outdoor sports to be curtailed, emergency heat lines to be activated, and workers to go door-to-door checking on the elderly and at-risk.

Where it stands: Arsht-Rock and its two-year-old Extreme Heat Resilience Alliance are pressing the National Oceanic and Atmospheric Administration (NOAA) and the World Meteorological Organization to make naming and ranking of heat waves standard practice.

  • NOAA operates the U.S. National Weather Service, which — so far — favors early warning systems but not a naming system.
  • The National Weather Service tells Axios that while it "does not name heat waves," it does "appreciate the value of continued research and engagement to further our understanding of and response to extreme heat and other weather events."

Meanwhile, California could soon become the first U.S. state to set up a system for early warning and "ranking" of extreme heat events.

  • Relevant legislation passed unanimously in the state Assembly will soon be considered in the state Senate.

The idea for a statewide early warning system originated in a report by the California insurance commissioner.

  • "California’s 'red flag' warnings for wildfire conditions, the U.S. Environmental Protection Agency's Air Quality App, and the naming system for tropical storms and hurricanes by NOAA could serve as templates for naming and ranking heat waves," reads the report.

What's next: In July, Arsht-Rock will release projections about the expected mortality of heat in 13 cities, plus new data about heat's impact on worker productivity.

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