LAS VEGAS — Cristian Sanchez’s crew was on the job site by 6 a.m. Saturday, when Las Vegas was just a balmy 90 degrees.
The eight landscapers were dressed for battle. Long-sleeve reflective orange shirts with hoods. Bandannas and face masks. Baseball caps and broad-brimmed hats. Sanchez, from Veracruz, Mexico, has spent six years as a landscaper in Las Vegas, and he knew what it looked like when heat became overwhelming.
“Vomiting. The loss of strength,” he said. “When I first began working this way, I felt the heat, with a lot of headaches. But over time, one gets used to it, your body gets accustomed to the heat. And it becomes normal.”
The Las Vegas heat — with highs remaining well over 100 — was part of a significant heat dome that has been crowding weather maps over the Lower 48 states for the past week, bringing blistering temperatures that have toppled records. Highs have spiked 10 to 20 degrees above average in spots, and some places have endured their hottest and most humid weather ever observed during June. More than 95 million Americans are under excessive heat warnings or heat advisories from the Florida Panhandle to northern Michigan.
For researchers studying extreme heat in the Southwest, Sanchez falls neatly into a particularly high-risk category for heat-related illness and injury. A study published last month in the International Journal of Environmental Science and Technology that looked at the effects of extreme heat on the health of the outdoor workforce in Nevada, California and Arizona found that heat morbidities increase with years of service on the job. Workers with more than five years of service were at greater risk than those with less than one year of service to suffer a heat-related illness.
“That was not expected,” said lead author Erick Bandala, assistant research professor of environmental science at the Desert Research Institute in Las Vegas. He said he had thought newer, unexperienced workers would face the biggest problems. But data from the Bureau of Labor and Statistics between 2011 and 2018 suggest otherwise, he said.
Bandala said that the accumulation of years of heat stress and exhaustion may account for the findings, or that workers become inured to the threat, even as climate change, driven by the burning of fossil fuels, makes heat waves more frequent and more intense.
“After a while of doing the same thing and not feeling affected that badly, they probably get overconfident,” Bandala said in an interview. “You forget about the risk you’re exposed to.”
The study, in conjunction with Nevada State College and the Guinn Center for Policy Priorities, also found that over the past decade, the summertime heat index — a combination of temperature and humidity to measure how heat feels to the human body — rose significantly in both Las Vegas and Phoenix, climbing from a level deemed “extreme caution” in 2012 into the “danger” zone by 2018. The number of nonfatal heat-related injuries and illnesses in all three states increased steadily in that time, to above the national average.
“We all know that when flash flooding or thunderstorms or hurricanes are coming, we better take care of ourselves,” Bandala said. “But not really about extreme heat. It’s probably one of the most under-considered risks that we can be facing.”
For the world, the last seven years have been the seven hottest on record. The Southwest has been enduring a crippling drought for two decades, forcing unprecedented water shortages and shriveling reservoirs to record lows. The arriving summer brings the prospect of more extreme heat waves like the record-shattering heat dome last year in the Pacific Northwest.
Extreme heat is already the deadliest type of weather disaster in the country, one that hits hardest on low-income and minority communities that are hotter — with more pavement and less greenery — and tend to have buildings with worse ventilation and less access to air conditioning.
In Las Vegas, the frequency and intensity of heat waves have increased over the past decade, a trend that correlated with the number of heat-related deaths, according to a 2019 study by Bandala and his colleagues.
Over the past five years, 570 people have died of heat-related causes in Clark County, which has more than 2 million residents and includes Las Vegas. In the five years prior, 2012 to 2016, 241 people died of heat, according to data from the Southern Nevada Health District.
For those who work outside, there is little choice but to persist despite extreme heat.
Jose Martinez, a 47-year-old landscaper from Jalisco, Mexico, watched a colleague collapse from heat exhaustion on Thursday.
“He got overheated. He had just arrived from Mexico. He wasn’t acclimatized,” Martinez said on Saturday as he worked outside Carmel Cliff, a gated community in Summerlin, on the west side of Las Vegas. It was 11 a.m. and 106 degrees. “He needs time to get used to it. It hit him and he lost strength. We said, ‘Go to your house.’ We try to take care of each other. We don’t want to let him die.”
Parts of the Las Vegas metropolitan area are among the fastest-growing places in the country. New subdivisions and gated communities are rising across hills to the west of the city. Blue flags flutter in the hot wind at new construction sites promoting model homes. Signs and billboards tout “new homes selling now” and open houses in the sprawling desert suburbs.
“There’s a lot of work here,” Martinez said. “Thank God.”
He has spent nearly three decades doing outdoor work and says he’s adapted to the heat.
“When there is need, there is no choice,” he said.
Over the past decade, the highest annual death toll from heat in Clark County came last year, when 153 died, a rate of 6.4 deaths per 100,000 residents. A quarter of those were homeless.
By noon Saturday, the temperature hit 108 degrees and hundreds of people crowded under fans at the Courtyard Homeless Resource Center, one of several cooling centers across the city. During last summer’s record-breaking July heat wave, authorities encouraged homeless people to leave the open-air shelter because nighttime temperatures remained dangerously elevated.
It was loud and chaotic as people clustered around a water spigot and people yelled at each other under the punishing sun.
“Take a look around,” said Patrick Dewone Jones Sr., who had been living at the shelter on and off for a year. “The heat is getting to them. The heat makes people more aggressive, more meaner, more irritable.”
Jones, 51, said there are fights nearly every night as people jostle for space in the crowded facility. He drinks the warm tap water from the faucets because the alternative is “dehydrate and die.”
“Everybody is on top of everybody trying to get some cool air and trying to get some shade,” he said. “If you sit in somebody’s spot, it’s trouble.”
On Saturday, volunteers with Las Vegas Liberation, a local aid group, handed out bottled water from coolers of ice.
“It feels like it’s getting hotter earlier in the year, and stays hotter longer,” said Tyler Teresi, 25, one of the volunteers. “I’ve worked at some of the shelters before and people will come in just exhausted, clear heat stroke.”
A Black woman approached him just after the last of the roughly 300 water bottles had been passed out. Teresi apologized.
“We just have ice left,” he said.
Matthew Cappucci contributed to this report.