Dehydration is already the leading cause of death among migrants crossing the border from Mexico to the US, and conditions will worsen as the climate continues warm, according to a new study published earlier this month in Science.
The study looks at the part of the country commonly used by migrants crossing the border between Nogales in Mexico and Three Point in Arizona. Researchers have compiled a database of deaths in the region spanning nearly 40 years and narrowed it down to the warmest months of the year between May and September. They then used a biophysical model of human dehydration to calculate which points along that section would be the most deadly, comparing them to a map of 93 deaths in their data set; most of these deaths, the researchers found, correlated with areas of the map where people would experience the most dehydration.
“We provide the first empirical evidence that the physiological stresses experienced by people trying to cross the Sonoran Desert in the United States are sufficient to cause severe dehydration and related conditions that can lead to death,” said Ryan Long, associate professor of wildlife science at the University of Idaho. , He said in the news. “[A] a disproportionately high percentage of migrant deaths occur in areas where projected water loss rates are highest. ”
While people who cross usually carry water, the average amount they bring it is not enough to prevent the most severe cases of dehydration, research has shown.
“Access to sufficient amounts of drinking water to support high rates of water loss during travel probably makes the difference between life and death for many migrants,” Long said.
To better illustrate conditions people may face when making the dangerous crossing, the study quotes people who emigrated from Mexico to the U.S., who describe the challenges of their journeys.
“We were dying of thirst,” Lucho, a 47-year-old migrant from Jalisco, Mexico, said in Interview from 2009. “I was hallucinating at the time. We were surrounded by land, but I kept seeing water everywhere in the desert. ”
Thermal conditions at the border will only get worse with climate change. Arizona is the fourth fastest warming state in the U.S. and is already seeing it 50 dangerous thermal days a year, which should become 80 days by 2050. To better understand how much more dangerous border crossings will become, researchers clogged models of future warming in the region, based on a medium-term climate forecast, in the water loss model during the route walking scenario.
“We believe that migrant travel will become significantly more dangerous over the next 30 years,” said Reena Walker, a graduate student at U of I and co-leader of the study. Their calculations suggest that by 2050. people crossing the border on foot will have at least a 30% increase in water loss during travel due to higher temperatures.
The exploration comes during a particularly turbulent period at the border; in August, the U.S. Border Patrol reported almost 200,000 encounters with migrants along the border in July alone, a record in 20 years. CBP also reported 470 dead migrants at the border between January and October this year, the highest number since 2005; 43 bodies were found after a terrible heat wave in Arizona in July.
While migration between the US and Mexico is complex and influenced by many factors, climate change is definitely forcing migration, including the impact of extreme weather events, such as two consecutive hurricanes last year, as well as displacement due to crop failure and drought. The crisis on the American border is not the only one that has been aggravated by the climate. The UN last year defined climate change as a new threat that is already displacing people around the world, which it will only get worse as the world warms up.