Phoenix is expected to get another heatwave this week, after the city has already suffered under high temperatures that surpassed 110°F for a national-record of 31 consecutive days through Sunday.
While extreme heat affects everyone, the harms fall most on people experiencing homelessness and lower-income families who are more likely to lack access to air conditioning. Sitting or falling on the sidewalk is especially dangerous, because pavement absorbs heat and can reach temperatures of 180 in Phoenix, causing severe burns.
"Unhoused people accounted for about 40% of the 425 heat-associated deaths tallied last year in Maricopa County, home to Phoenix," the Associated Press recently reported.
"If this continues, we will see more heat-related deaths," Amy Schwabenlender, head of the Human Services Campus, a medical and social services center near "The Zone," an area where Phoenix's homeless population is clustered, told the news agency AFP earlier this month. "It is a life-and-death situation."
Unequal access to air conditioning is just one of the many ways that the growing effects of climate change have the biggest implications for the least advantaged. Here are some others.
Urban heat islands
More than 40 million Americans in cities are experiencing far more intense heat than those in rural areas thanks to urban "heat islands," according to an analysis released last week by the nonprofit research group Climate Central. Temperatures can be more than 8 degrees Fahrenheit warmer than in nearby rural environments.
Urban heat islands are created in cities where open land has been replaced with buildings, concrete sidewalks, paved parking lots and other materials that absorb and retain heat.
Due to fewer heat-reducing amenities like parks, yards and street trees, low-income neighborhoods and communities of color are more likely to be in severe heat islands. Baltimore's Franklin Square, a high-poverty, majority-Black neighborhood, is hotter than about two-thirds of the neighborhoods in the city and roughly 6 degrees hotter than Baltimore's coolest neighborhood, according to a 2019 investigation by NPR and the University of Maryland's Howard Center.
Outdoor work
Those in blue-collar occupations are far more likely to work outdoors in extreme heat. "Extreme heat poses a major health risk for outdoor workers, like UPS delivery people," Fortune reported last Friday. "Videos of drivers passing out have spread across social media."
As Voice of America noted last year, for many hourly workers, in the construction industry, even having the work day shortened in extreme heat has a downside, as it means lower earnings.
Wildfire smoke
Much of the northern United States has been dealing with air pollution caused by smoke drifting from hundreds of Canadian wildfires.
Low-income and communities of color have higher baseline rates of particle pollution because they are often near air pollution sources like highways and ports.
"Whether it's diesel trucks and buses in people's neighborhoods, commuter cars or power plants — there are a lot of communities that have already been impacted by air pollution," Sacoby Wilson, a public health professor at the University of Maryland, told Yahoo News last month. "This additional pollution from wildfires is making that situation worse."
This dangerous combination of brutal heat and wildfire smoke can lead to a variety of health effects ranging from asthma to reduced lung function, cardiovascular disease and death.
Flooding
Since warmer air holds more moisture, rainfall has been increasingly extreme in recent years, leading to flash floods like those that have recently killed residents of Pennsylvania, New Yorkand Vermont.
Due to lower-quality infrastructure, poorer communities are more vulnerable in floods. This is especially true in developing countries. Last September, flooding in Pakistan killed over 1,700 people, in part because buildings, roads and power lines are less fortified than in rich countries and weather tracking and emergency services are less advanced. (Flooding has already killed 55 Pakistanis this year.)
Last year, when flooding killed 13 New York City residents, 11 were in basement apartments. These often-cramped, illegal units are relatively affordable, due to their lack of light and air, but are more susceptible to flooding.
Sea-level rise caused by melting polar ice caps is also contributing to stronger hurricanes. In 2005, Hurricane Katrina the mortality rate among Black residents of Orleans Parish was up to 4 times as high as for white residents, according to the National Institute for Health, because many lower-income residents lacked the means to evacuate.
Solutions
Cities are beginning to address the threat from extreme heat. Eight cities around the world have appointed chief heat officers, including Miami, Los Angeles and Phoenix to coordinate heat preparedness and response.
Phoenix is opening air-conditioned cooling centers, arranging transportation to get the carless to them, and sending out volunteers with water bottles. It is also embarking on new strategies to reduce the urban heat island effect, such as painting pavement lighter colors that reflect heat instead of absorbing it.
To preserve access to air conditioning, some experts argue that utilities should be prevented from shutting electricity use for nonpayment in the summertime and that the federal government should subsidize electricity use for low-income households in the same way that it does home heating fuel.
"It's clear that we need to act now to develop a nationwide framework for climate adaptation to protect all vulnerable families from hotter summers, higher bills and more extreme weather events," Mark Wolfe and Cassandra Lovejoy, the co-directors of the Center on Energy Poverty, wrote last Thursday in CNN.