One of the largest disaster relief agencies on Tuesday had a message for the world’s mayors: Heat waves are getting more intense on a hotter planet, but they don’t have to be deadly if city officials take simple and often inexpensive steps.
The International Federation of Red Cross and Red Crescent Societies put out a 96-page guidebook designed to help city officials prepare for heat waves. It repeatedly points out that heat waves are predictable, sometimes days and weeks in advance, and that city officials, and, sometimes private employers, can take steps to save lives.
The tips include what the federation’s president, Francesco Rocca, described as “really simple and affordable” measures. They include knowing when a heat wave is coming; letting people know how dangerous that can be, especially in normally hot places where people might try to shrug off a heat wave; preparing health workers to respond to a health emergencies; setting up cooling centers for those without access to air conditioning; and distributing water.
Last month was the hottest June in 139 years of record-keeping, according to NASA. If the emissions of heat-trapping gases continue to increase at the current pace, the United States is projected to have twice the number of extremely hot and humid days that feel like at least 100 degrees Fahrenheit, or about 38 degrees Celsius, according to a study by researchers at the Union of Concerned Scientists.
Kristina Dahl, the lead author, said the study pointed to “a hotter future that’s hard to imagine today.”
Heat waves are most dangerous for those who are already at risk, including older people and the poor. The Red Cross guidebook calls on city governments to identify in advance neighborhoods and communities that may be more at risk and, then to create ways to check on vulnerable people during spikes in heat.
After a deadly heat wave in 2003, Paris directed social workers to do just this. It helped to prevent mass deaths in subsequent heat waves, including the latest one a few weeks ago.
“Heat waves are silent killers,” Mr. Rocca said Tuesday at a news briefing at United Nations headquarters in New York. “They take the lives of people who are already vulnerable.”
The guidelines also include recommendations to prepare cities for more record-breaking hot days over the long term, for example by painting rooftops and sidewalks in reflective white paint. The book directs one recommendation at employers: Companies, it said, should “add heat waves to their list of occupational hazards,” and especially make allowances for outdoor workers to rest during peak heat hours.
With industrial emissions having increased average global temperatures over the last 150 years, scientists say heat waves are becoming more frequent and longer-lasting. Heat records are being broken in cold and hot places and the heat spikes that were once considered rare are becoming more frequent. The worst heat waves in Europe over the last 500 years, for instance, have all come in the last 17 years.
Especially dangerous for human health is when nighttime temperatures don’t drop sufficiently to allow the body to cool down. In the United States, summer nights have warmed at nearly twice the rates of summer days.
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