Heat waves are a silent killer. Unlike other extreme weather phenomena, you can’t see them coming, and they don’t leave behind a trail of destruction. But they kill more people than any other weather hazard in the country and exact a greater toll in the developing world. And they are getting worse because of climate change.

What if we named and ranked them, as we do tropical storms, to increase their visibility and raise awareness of their danger? A new, international coalition put together by the Adrienne Arsht-Rockefeller Foundation Resilience Center has declared naming and ranking heat waves its “number one priority.”

For decades, public health, weather and climate experts have grappled with how to raise public awareness of heat waves and the understanding of their threat. The 1995 Chicago heat wave killed more than 700 people. The 2003 European heat wave was blamed for as many as 70,000 excess deaths. More than 50,000 people died in a heat wave in 2010 in Russia.

Because of the buildup of greenhouse gases in the atmosphere from human activities, heat waves are becoming more frequent, intense and longer-lasting, a trend predicted to continue in the coming decades. A study last year found a fingerprint of climate change in excessive heat events worldwide. Another recent study showed hot weather close to exceeding the limits of human survivability in some areas.

The call to name and rank heat waves originates from the Extreme Heat Resilience Alliance, launched this week. Its members include emergency response organizations such as the Red Cross Global Disaster Preparedness Center; science research hubs such as the National Center for Atmospheric Research; several cities, including Athens, Mexico City, Miami and Tel Aviv; corporations, nonprofits and reinsurers. It is supported by a $30 million grant from the Rockefeller Foundation, one of the largest climate donors in the United States, as well as the Atlantic Council, a D.C.-based think tank, which hosts the center.

The center has a goal to reach 1 billion people with climate resilience solutions by 2030 and sees addressing the increasing risk of heat waves as a key area to help accomplish it.

“Naming heat waves is the clearest way to communicate the dangers and severity of this risk which is growing,” Kathy Baughman-McLeod, director of the center, said in an interview.

Baughman-McLeod said the idea to name and rank heat waves originated from the California Climate Insurance Working Group, in which she participates. It is headed by Ricardo Lara, California’s insurance commissioner, who has joined the alliance.

According to a news release announcing the group, Lara will pursue the naming and ranking of heat waves for the state of California.

The alliance’s goal, Baughman-McLeod said, is to “push the conversation” toward a naming and ranking system for heat waves, working through a web of state, local, and international institutions involved in public health, science and policy. This includes the National Weather Service and the World Meteorological Organization, which oversees tropical storm naming.

“There’s this international cooperation that needs to be built the way it’s been built for hurricanes,” she said.

A long-standing challenge officials have faced in reducing the toll from heat waves stems from the fact the those most likely to be adversely affected are the least likely to be equipped to take action. The most vulnerable groups include those with mental illness, the socially isolated, older adults living alone, low-income families and the homeless. Lacking access to air-conditioning is a particularly high-risk factor.

“I think the naming creates a media opportunity for a more dramatic awareness [and] a more dramatic call for preparation and for action,” Baughman-McLeod said, noting that the naming of tropical storms has brought more resources into communities. “We don’t have the decision-maker awareness to protect and prepare people for extreme heat. That’s what this is about.”

The alliance isn’t just putting a naming proposal forward. It’s also seeking to better assess the cost to cities of dealing with heat waves and change the way public health data is recorded to more easily track heat-related illnesses and deaths.

Another program on its agenda is to create forecast-based public insurance mechanisms that could get cities access to funds for purchasing generators, pop-up cooling stations and other equipment if they know that a major heat wave is on its way.

Qualified praise from outside experts

Weather, climate and health experts have generally reacted favorably to the naming and ranking proposal.

Ed Maibach, a public health expert and director of George Mason University’s Center for Climate Change Communication, says that heat waves are an “abstraction” since they cannot be seen and that naming them would render them more concrete and actionable.

“Heat waves are dangerous,” he wrote in an email. “Making them more concrete is a useful way to help people understand the dangers, act on the dangers, and share information with other people about the dangers.”

Brenda Ekwurzel, director of climate science at the Union of Concerned Scientists, agreed that heat waves demand more attention.

“Exploring a scientifically robust way to rank heat waves that people can readily understand as shorthand that can help saves lives is critical,” she wrote in an email.

In the 1990s, Philadelphia dealt with several killer heat waves and responded by initiating early warning and intervention systems to deal with the problem, which were credited with saving lives. Gary Szatkowski was the head of Philadelphia’s National Weather Service office as these responses were rolled out. Szatkowski, now retired from the NWS, also thinks the idea of naming heat waves deserves consideration.

“[I]f naming heat waves would help communities in their efforts to develop effective excessive heat mitigation programs, it is worth having the conversation,” Szatkowski said via an email.

Some experts, however, raised questions about how heat wave ranking and naming would be executed and whether it would be effective.

“Naming events does not convey anything about the nature of the specific risks or impacts nor does it help nuance understanding of how those vary by a range of population characteristics — much less convey anything about the science,” Susan Jasko, a professor specializing in weather communications at the University of Alabama, said in an email. She stressed that any naming initiative should be a part of a larger strategy to educate different audiences about the hazard.

Larry Kalkstein, a professor emeritus at the University of Miami and an expert on heat and human health, expressed support for naming heat waves to raise awareness but said ranking them would be “problematic.”

“[T]he definition of a major heat event varies from one professional organization to the next,” he wrote in an email. “Is maximum temperature more important than minimum temperature? Is duration of the event most important? Our research finds that early summer heat events are more damaging to health than late summer heat events. How do you account for this in the rankings?”

Kalkstein said the fact that heat affects people in different parts of the country differently must be taken into account, as well. “It is always important to understand that the impact of heat is relative, not absolute,” he wrote. “An excessive heat event in Duluth is very different than a similarly hot event in Dallas.”

Baughman-McLeod acknowledged that the alliance’s biggest challenge will be to define exactly what a heat wave is.

“We know there are questions to be answered around how to define a heat wave,” she said. “We need to build a framework that’s robust enough to be meaningful. The [heat wave] threshold needs to be at the right level and frequency, knowing there will be questions to get answered. It won’t be perfect, but we’ll refine it and learn as we go.”

Models to follow include Britain and Ireland

in building its campaign, the alliance could learn from the experiences and lessons of naming tropical and winter storms.

Whereas the long-standing tradition of naming tropical storms has been considered a success, naming winter storms has been mixed.

When the Weather Channel began naming winter storms in 2012, many meteorologists protested. Some dismissed it as a marketing scheme and criticized the network for not coordinating with the National Weather Service. Others took issue with the network’s criteria for naming storms.

A study led by Adam Rainear, a professor at West Chester University, evaluated the effectiveness of the Weather Channel’s storm naming. It found “little difference exists between individual perceptions dependent on whether a name is used or the type of name used.”

But the naming of winter storms in England and Ireland, led by the governments’ meteorological agencies, has been seen more favorably.

“[T]he UK Met Office and Met Éireann view naming winter storms as a very effective preparedness tool,” Szatkowski said.

Evelyn Cusack, head of forecasting at Met Éireann, said: “The naming of storms by National Met Services as well as color-coding weather warnings provides a clear, authoritative and consistent message to the public and prompts people to take action to prevent harm to themselves or to their property.”

Government involvement in such an effort seems critical. At the moment, though, the National Weather Service says it is largely sitting this out. The World Meteorological Organization did not respond to a request for comment.

“The Foundation contacted us about their effort to establish an Extreme Heat Resilience Alliance and name heat waves, however, we are not considering naming heat waves,” Maureen O’Leary, a Weather Service spokeswoman, said in a statement. “There are a number of challenges associated with defining heat waves and criteria for categorization, as well as communications challenges as heat conditions can vary widely and over a very large area.”

However, the Weather Service is leaving the door open to considering a naming system in the future.

“We appreciate continued research and engagement such as that of the Foundation to further our understanding of and response to extreme heat events. While we do not plan to name heat waves, the National Weather Service continues to learn from social and physical science research to fully understand the implications of a heat event naming convention,” the statement said.

Andrew Freedman contributed to this report.