Metro Phoenix has so far seen twice as many heat deaths as this time last year. Authorities are trying to understand why and how to intervene.
Transcript
SACHA PFEIFFER, HOST:
A recent NPR investigation found that heat-related deaths are vastly underreported across most of the U.S. One place that does track these fatalities closely is scorching hot Phoenix, Arizona. This year, the number of heat-related deaths there appears to have jumped significantly. Here to tell us more is KJZZ’s Katherine Davis-Young. Hi, Katherine.
KATHERINE DAVIS-YOUNG, BYLINE: Hi there.
PFEIFFER: So just how significantly are heat-related deaths up in Phoenix this year?
DAVIS-YOUNG: They’re up 76% from the same point last year. So far, 275 heat-related deaths are confirmed in Maricopa County, and more than 500 deaths are still under investigation as potentially heat related.
PFEIFFER: So if 275 are confirmed, maybe 500 might eventually be confirmed, that could be more than 700 heat-related deaths. How close would that get you to a record?
DAVIS-YOUNG: Well, the most heat-related deaths ever confirmed in a single year was 645. That was back in 2023. The county medical examiner told me he doesn’t expect we’ll break that record this year, but it could be a close second or third place. But these numbers had been falling since 2023, and health officials consider all of these deaths to be preventable. So any increase, especially after a couple years of decreases, is really troubling.
PFEIFFER: It has obviously been very hot in parts of the country, but just because it’s hot doesn’t mean people have to die. So why do the numbers appear to be so much higher this year?
DAVIS-YOUNG: One thing we know for sure is that dangerous heat started earlier in the year than ever before. Most of the western U.S. this year had this record-shattering, climate change-fueled heat wave in the early spring. In Phoenix, that meant we had our first 100 degree day in mid-March, about six weeks earlier than usual and long before the city usually opens up any cooling centers or other types of heat relief efforts.
PFEIFFER: A hundred degrees in March – that was just springtime. So by the time Phoenix got to summer, what did temperatures look like?
DAVIS-YOUNG: Yeah, this was our second hottest summer on record, and most of the record-shattering heat that we experienced this summer actually happened overnight. So here’s Maricopa County medical examiner, Dr. Jeff Johnston.
JEFF JOHNSTON: It seems to be those overnight lows that aren’t getting below 90, particularly on consecutive days, that seems to be riskiest.
DAVIS-YOUNG: So those lows above 90 degrees used to be really rare in Phoenix. On average, the city used to get about seven nights per year in the ’90s, but those numbers have skyrocketed. This year, we had 29 nights that hot.
PFEIFFER: Interesting. During the day, people might be in an air-conditioned office, but in evening, you might not have that option. Is this a Phoenix phenomenon, or how much is this a broader trend?
DAVIS-YOUNG: Well, according to the research organization Climate Central, that rapid warming of summer nights is a result of climate change and urbanization, and it’s happening in almost every city in the U.S. And like medical examiner Johnston said, it’s a big public health concern. He told me during one of these heat waves with this round-the-clock hot temperatures this summer, he saw one of the biggest spikes in heat relief deaths – or heat deaths ever.
PFEIFFER: Are Arizona and Phoenix trying to do anything in response?
DAVIS-YOUNG: Well, we talked about the problem of this overnight heat. The city of Phoenix has spent millions of dollars over the past few years to expand hours at cooling centers. City officials say they are confident that that investment is saving lives, but whether or not they’ll be able to scale up those kinds of resources in years ahead remains a big question. A lot of these sites have been funded through pandemic-era federal aid, which runs out at the end of this year.
PFEIFFER: That is KJZZ’s Katherine Davis-Young. Thank you.
DAVIS-YOUNG: Thank you.
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