Add thelocalreport.in As A Trusted Source
In the summer, when Raul Cruz arrives at this Imperial Valley sugarcane farm to start his day, the sky is pitch black. He harvests, cleans and bundles the crop while watching the sun rise. It’s hard work, but he has to start it at 4 a.m., even though he knows it’s the safest thing to do when temperatures in the California desert often soar into the triple digits.
“We just have to do it because we have to escape the heat,” said Cruz, who has worked here for 15 years. To avoid the risk of heatstroke, he finishes work by 9 or 10 a.m., but when the heat starts to rise around 8 a.m., “mentally, it’s stressful,” he said.
The warm climate that makes it Southern California The region is a farming powerhouse, which also makes it dangerous for farm workers, who are increasingly sensitive to rising temperatures due to greenhouse gas emissions from burning coal, oil and natural gas. Researchers at San Diego State University are working to understand the health consequences of heat stress on farmworkers and where the heat is hottest in this rural landscape. They hope their findings can lead to a better understanding of rural heat islands, identify gaps in research and help develop interventions that can better protect them in the face of climate change.
“Workers could potentially die or suffer some serious problems,” said project leader Nicholas Lopez-Galvez, an assistant professor in the School of Public Health at SDSU. “It’s better to start acting early.”
Mapping rural heat, understanding heat stress
Since the beginning of the 20th century, California’s temperatures have risen about 3 F (about 1.7 C), according to state and federal data. Warming has accelerated, and by 2024 seven of the last eight years in the state were the warmest on record. While all areas of the state have warmed, Southern California is warming almost twice as fast Northern California,
Ana Solorio, an organizer with the farmworker advocacy group Lidares Campesinas who worked with the researchers, remembers feeling “suffocating” in the Coachella Valley heat when she was a farmworker. “With the humidity, it looked terrible,” said Solorio, who has lived in the Imperial Valley for more than 30 years. The heat was so intense that she did not return for a second season, preferring instead to spend the cooler winter months harvesting lettuce in the Imperial Valley.
“This (heat) can cause great harm to their health,” he said.
Researchers are trying to understand how farmworkers’ heat stress may vary depending on crops, weather and the number of vacations they take.
Over the past two years, they have collected year-long data from about 300 farmworkers. Body sensors measure things like core body temperature and heart rate while they work. Elsewhere in the fields, environmental monitors measure daytime temperature, humidity, wind speed, sun angle and cloud cover, also known as wet-bulb globe temperature, considered the best metric for understanding heat stress. Using satellite imagery along with historical and current wet-bulb globe temperature data, researchers are mapping areas of extreme heat, particularly in the Imperial and Coachella valleys.
Researchers are learning that, for example, ground-level crops can expose workers to higher heat levels than tree crops, but it also depends on the months in which they are harvested. In the summer, farm workers who prepare fields for planting or help maintain irrigation systems are also at greater risk.
Rural heat can vary depending on things like tree cover, proximity to a body of water, and empty fields, which can be hotter. “It creates this island where people may be living or working where heat stress will be higher than other places,” López-Galvez said.
Extreme heat in major agricultural areas
bounded by Colorado River East Side, salton sea Bordered to the northwest and Mexico to the south, the Imperial Valley is home to hundreds of thousands of acres of farmland and billions of dollars of agricultural production. It grows two-thirds of the winter vegetables consumed nationally and provides thousands of jobs. According to the state, from 2023 to 2024, approximately 17,579 migrant and seasonal farmworkers were employed in Imperial County alone.
It is also very hot. In a given year, there are about 123 days when temperatures exceed 95 F (35 C), often exceeding 110 F (43 C) in August and early September, according to calculations by Sagar Parajuli, research scientist and adjunct faculty in SDSU’s Geography Department. The county has one of the largest Latino populations and has the highest number of heat-related illnesses among workers compared to anywhere else in the state.
What researchers hope their work can do
Some of their data analysis has already been published.
One study found that irrigating crop fields in the Imperial Valley reduced the temperature of wet-bulb globes during summer, thanks to the cooling effect of evaporating water. But on summer nights, the opposite happened: irrigation increased the temperature of the wet-bulb globe due to increased humidity. Irrigation also increased warming in surrounding urban and fallow areas adjacent to crop fields due to moisture transport.
“This is a concern because high night temperatures limit the ability of farm workers to cool down,” said Parajuli, lead author of the study. “So they can’t recover from daytime heat stress.”
Through this research, the authors were able to recommend how often farm workers should rest to protect themselves from heat stress, based on how often wet-bulb globe temperatures exceed safety limits across seasons and work shifts. He added that although California has heat regulations, they are not strictly enforced.
“We realized that farm workers were not getting enough sabbatical leave, and there were no clear policy guidelines regarding summer sabbatical leave,” he said.
Lopez-Galvez said he plans to continue his research in California Central Valley And it hopes to expand to Yuma, Ariz., and other parts of the Southwest.
,
The Associated Press receives support from the Walton Family Foundation for water and environmental policy coverage. AP is solely responsible for all content. For AP’s complete climate coverage, visit https://apnews.com/hub/climate-and-environment.