Cities look for new ways to keep people safe — and alive — as extreme summer heat looms

More than five weeks remain before summer’s official start, but preparations for extreme heat have been underway for many months in parts of the country hit hard by last year’s sweltering conditions.

“We prepare for heat year-round in Phoenix,” Mayor Kate Gallego said. “It’s something that we know is coming, so we have to think about it even on the coldest day of the year.”

But last summer was especially severe — Phoenix, for example, endured 31 consecutive days of high temperatures at or above 110 degrees Fahrenheit, breaking a previous record of 18 days set in 1974. At least 645 people in Maricopa County, which includes Phoenix, died from heat-related causes in 2023, a 52% increase over the previous year, according to the county's Health Department.

The 2023 heat waves revealed how challenging it can be to cope with extreme temperatures for weeks on end, even in places where residents are accustomed to warm weather. And the months ahead are expected to be just as hot — if not hotter.

The National Oceanic and Atmospheric Administration said Thursday that based on global temperatures so far, 2024 will rank among the five warmest years in recorded history and has a 61% chance of being the hottest on record.

That has prompted cities across the South and the Southwest to re-evaluate how best to keep people safe — and alive — this summer. Some have launched new initiatives aimed at increasing shade in public spaces, strengthening health care systems to deal with victims of heat waves and doing outreach with outdoor workers, homeless populations and other vulnerable communities.

Gallego said Phoenix has been creating “cool corridors” by planting trees and resurfacing the pavement with more reflective coatings to reduce urban heat. A primary focus right now is mitigating high overnight temperatures, which plagued the city last summer.

“We were getting low temperatures that were setting records for how hot they were,” she said. “That’s really pushing us to focus on how we design the city — what materials we use and how we protect open spaces, which tend to dissipate heat at night.”

In Florida’s Miami-Dade County, chief heat officer Jane Gilbert said a key priority is channeling resources to protect residents who are most vulnerable to temperature spikes.

“It’s people who can’t stay cool at home affordably, it’s people who have to work outside, it’s the elderly, it’s people who have to take a bus on a route where they might have to wait at an unsheltered stop for over an hour in that heat,” she said.

To that end, the county’s Transportation Department installed 150 new bus shelters last year and is expected to add 150 more this year, according to Gilbert. With a $10 million grant from the Inflation Reduction Act, the office is also planting trees along roads maintained by the county and the state to increase shade.

Gilbert’s team has focused on raising awareness among renters and homeowners about affordable ways to cool their spaces. Her office also tries to educate employers about the importance of protecting their workers and holds training programs for health care practitioners, homeless outreach workers and summer camp providers.

Nationally, heat kills more people than any other extreme weather event; it’s often referred to as a “silent killer” because heat’s impact on the human body is not always obvious.

“When a hurricane hits or a wildfire comes through, there’s no doubt about what just happened, but heat is more difficult because, for the most part, we don’t have those same context clues in our environment until it gets so extreme,” said Ashley Ward, director of the Heat Policy Innovation Hub at Duke University’s Nicholas Institute for Energy, Environment & Sustainability.

Ward and her colleagues specialize in “heat governance,” helping local and state governments prepare for extreme heat events. The work includes finding ways to mitigate heat and develop emergency responses for major heat waves.

In North Carolina, for example, Ward and her colleagues have helped counties craft heat action plans to identify their most vulnerable populations.

She said government officials should treat onslaughts of high heat and humidity similar to hurricanes, tornadoes and other disasters.

“People in emergency management and public health have a lot of structures in place already for all kinds of other extreme weather events, but not so much for heat,” Ward said.

Last summer was a wake-up call, she added.

“That was our category 5 heat event,” Ward said. “The extreme nature of what we saw last summer was enough to focus attention on this topic.”

Climate change is increasing the frequency, duration and intensity of heat waves around the world, studies show. Last year was the planet’s hottest on record, and the warming trend continues. April was the 11th consecutive month with record-breaking global temperatures, according to the European Union’s Copernicus Climate Change Service.

In much of the U.S., temperatures over the next three months are expected to be above average, according to NOAA.

Ward said that it’s heartening to see cities take extreme heat seriously but emphasized that major challenges lie ahead. For one, preparing early for extreme heat requires funding, which is a major challenge, especially for rural communities.

Even trickier will be addressing the underlying social issues that get magnified during heat waves, such as homelessness, rising energy costs and economic inequality.

Ward is optimistic, though, that last summer’s experience has catalyzed some local governments to act.

“What I hope we see going forward is more emphasis on what we can do to reduce those exposures to begin with," she said, "so that we’re not constantly in response mode.”

This article was originally published on NBCNews.com