There is an increasing effort to name and categorize heat waves as we do hurricanes – to draw attention to their importance, alert people to dangerous temperatures, and spur public officials to action.

Why is this important: Heat waves are the deadliest type of weather emergency in the United States. They are deadlier than floods, tornadoes or hurricanes – and their frequency and intensity are increasing due to global warming.

• Excessive heat – which hits low-income communities hardest – does not lend itself to dramatic television coverage, so people sometimes underestimate the risk.
• Proponents of a more formal public warning system say it could save lives and trigger measures such as opening community cooling stations and asking people to stay indoors.

Driving the news: This month, Seville, Spain is set 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 will 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 Los Angeles, for example, will look and feel very different from the same designation in Milwaukee.

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

Details: Under the warning system kicking off in the world’s six cities, ‘category one’ is the least severe, while ‘category three’ would be ‘the most terrible 10% of heat waves’, said Larry Kalkstein, chief heat science advisor at Arsht-Rock. .

• “For all three, we recommend staying indoors in the air conditioning as much as possible,” he told Axios.
• Each participating city “has a different set of formulas” that will determine what the categories look like, in part based on their city structure, Kalkstein said. For example: Philadelphia has many brick townhouses with black tar roofs that trap heat.
• Any of the designations would ideally prompt city swimming pools to open, outdoor sports to be curtailed, emergency heat lines to activate and workers to go door to door to check on the elderly. and at risk.

Where is it : Arsht-Rock and his two-year-old Extreme Heat Resilience Alliance are lobbying the National Oceanic and Atmospheric Administration (NOAA) and the World Meteorological Organization to make heat wave naming and classification standard practice. .

• NOAA operates the US National Weather Service, which – so far – favors early warning systems, but not a naming system.
• The National Weather Service tells Axios that while it “doesn’t name heat waves,” it “appreciates the value of continued research and engagement to deepen our understanding of and response to extreme heat and heat waves.” ‘other meteorological events’.

Meanwhile, California could soon become the first US state to implement an early warning and “ranking” system for extreme heat events.

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

The idea of ​​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 tropical storm naming system and NOAA hurricanes could serve as models for naming and classifying heat waves,” the report read.

And after: In July, Arsht-Rock will release projections of expected heat mortality in 13 cities, along with new data on the impact of heat on worker productivity.