David Dudley is the executive editor of CityLab. He is the former editor in chief of Urbanite magazine and a former features editor for AARP: The Magazine.
Hint: It helps to be young.
The 1995 heat wave that killed an estimated 739 people in Chicago was a terrifying but instructive event. “At the time, public health agencies considered heat waves a minor nuisance,” says the sociologist and writer Eric Klinenberg, whose 2002 book Heat Wave: A Social Autopsy of Disaster in Chicago chronicled a horrifying cascade of policy errors and social conditions during a three-day period of unrelenting heat and humidity in mid-July.
When the mercury started to climb, Klinenberg says, “the mayor was in his beach house.” So were several other key city officials. “No one felt compelled to come back and manage the crisis.”
Last year, Chicago Magazine assembled a grisly oral history for the 20th anniversary of the event, which offered an opportunity to appreciate why it hasn’t been repeated since (in the U.S., at least). Now, impending hot spells are greeted with abundant public health warnings, the opening of community cooling centers, and wall-to-wall extreme-weather media coverage more substantive than the egg-frying-on-the-sidewalk routines that once dominated local TV. “Far more cities now understand how dangerous the heat can be,” Klinenberg says.
Unfortunately, he adds, that’s about it for the good news. City dwellers face hotter days ahead, and the institutions and infrastructure that wilted in Chicago will be tested in longer, more intense, and more frequent heat waves. “The underlying issues behind why heat waves are so deadly have become more dire since the 1990s,” Klinenberg says.
This week and next, much of North America will be enjoying/enduring the highest temperatures of the summer, climatologically. It’s a good time to review the basics of avoiding becoming an urban heat casualty.
Don’t be old
It’s too late for some of us, but the best defense against heat illness is a healthy young cardiovascular system, ample hydration, and plenty o’ sweat. The elderly are far more vulnerable to the effects of long-term heat than young people are: Aging hearts strain to achieve the increased blood flow necessary for thermoregulation, and older people sweat less, too.
The vast majority of Chicago’s heat victims were over age 60. But, as Klinenberg’s work revealed, social isolation was the critical risk factor. Mortality rates were highest for elderly residents who lived alone, often without family or friends who lived nearby. Men were more than twice as likely to die as women, who tended to have more robust social networks.
Be a good neighbor
Your neighborhood matters, too: One reason only 2 percent of the Chicago victims were Latino was because the city’s Latino community was largely packed into densely populated areas, while African-American victims were often found in distressed parts of town with high vacancy rates and limited public services. Before they died alone, they’d long since been abandoned. Residents of low-income black neighborhoods with high populations and functional “social infrastructure” fared as well as affluent white neighborhoods. Some research also suggests that post-storm resiliency can bolster existing community bonds. “Ultimately, this isn’t about the weather,” Klinenberg says. “It’s about society. It’s about the way we treat each other.”
Get out of town
During the brutal August of 2003, the deadliest heat wave in history claimed tens of thousands of lives across Western Europe, including about 15,000 in France. Mortality was particularly high in Paris, where the urban heat island effect prevented nighttime temperatures from falling. One 2012 study that used thermal imaging to compare temps in Paris with those in a nearby suburb found that a half-degree Celsius difference in the average minimum nighttime temperature more than doubled the risk of death among older city dwellers.
Hope the power doesn’t go out
Not only was residential air-conditioning unavailable for many low-income Chicagoans, but high electrical demand strained the grid and left 49,000 city households with no power at one point during the ’95 heat wave. Blackouts triggered by surging A/C usage and summer storms will be increasingly common in our warming world, and the nation’s power infrastructure remains vulnerable. Climate change played an off-screen role in the September 2011 blackout that left San Diego sweltering without power for 12 hours—the outage was tripped by an Arizona wildfire that knocked out a transmission line on a 113-degree day.
But, as critics of the American appetite for air-conditioning continue to remind us, A/C is more problem than solution: “By making our world temporarily cooler, air conditioning is making it permanently hotter,” writes Stan Cox, author of Losing Our Cool: Uncomfortable Truths About Our Air-Conditioned World. He cites not only the enormous amount of energy consumed (about 5 percent of annual domestic electricity production) but its distorting impact on the built environment.
Over the past half-century, American cities have taken on an unstable thermodynamic form, coming to resemble collections of boxes full of cool air crowded onto concrete heat islands. Turn off the AC, and office buildings would become uninhabitable, vehicles sitting in traffic would become torture chambers, apartment buildings would become death traps.
Weaning Americans off their A/C and building more heat-tolerant cities will be an enormous undertaking. But there are a host of relatively modest changes, from building sun-reflecting cool roofs to pumping up the urban tree canopy, that can knock temps down a few critical degrees.
And, as Klinenberg says, we’ll need to figure this out: Living in denser, less resource-intensive urban areas is the sustainable way forward. “It’s one of the paradoxes of climate change,” he says. “We need more, bigger cities, but the more people [who] live in the city, the hotter they’ll be.”