The climate crisis is killing migrants trying to cross the US border, study finds
Undocumented migrants who attempt to cross the border from Mexico to the US are disproportionately dying in a harsh stretch of desert that is becoming deadlier due to the climate crisis, a new research has found.
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Migrants and asylum seekers trying to enter the US are often forced to traverse the harsh environment of the Sonoran desert in order to avoid border patrols and fortified crossing points. This hazardous journey is putting many of them under severe physical stress, according to researchers, with many dying in the heat due to dehydration and organ failure.
This risk will only intensify as the world heats up further due to human activity, with the research finding that in the next three decades migrants will become so dehydrated in the desert that they will have to carry 34% more water with them in order to survive.
“Crossing the border across these extreme environments is really dangerous for humans to do and in the next 30 years, with rising temperatures, it’s going to become even more extreme and push those levels to even further beyond what humans can actually sustain,” said Hallie Walker, a researcher at the University of Idaho and co-author of the research, published in Science. “It is incredibly dangerous.”
In the year to 30 September, US border agents apprehended more than 1.7 million people attempting to cross from Mexico into the US. Many of those who avoid arrest do so by taking on the daunting journey across the Sonoran desert, a rocky, scrubby expanse of land in Mexico and the southwestern US that oscillates between scorching heat in summer to freezing conditions in winter and contains more species of rattlesnake than any region in the world.
An estimated 350 people a year, many fleeing violence and persecution at home, die attempting this crossing, with some of these deaths due to suicide, exposure or car accidents. Researchers found, however, that a significant risk is the loss of fluids in a region where summer temperatures can reach 48C (118F).
Using a model that factored in the physical toll of making a journey from Nogales, a Mexican border city and Three Points, Arizona, the study found that people can succumb to the conditions within just a few days, with migrants often ill-prepared for the journey. The stress is highest for pregnant women and children, with the research finding that a pregnant women needs nearly 12 liters of water a day to survive making the trek in June.
Many do not get the adequate water and rest required, leading to deaths. The study found a “significant correlation between high levels of predicted evaporative water loss and the density of deaths” which “strongly implicate temperature and water availability as major contributors to broader patterns of migrant mortality during summer”.
The loss of water can cause disorientation and hallucinations, before becoming potentially fatal. The research cites interviews with migrants who explain how their toenails fell off during long hikes over the desert’s mountains or how they lost their eyesight and suffered chest pains as they struggled onward.
“Essentially the US is funneling individuals into places that they experience such extreme physiological stress that I, as an evolutionary biologist, couldn’t get approval from my university to put animals through the sorts of stresses that individuals are being put through,” said Shane Campbell-Staton, a researcher at Princeton and lead author of the study. “That’s how extreme these physiological stresses are.”
Migrants crossing the US’ southern border have become a political target in recent years, with Donald Trump instituting punishing detention and child separation policies, as well as a system known as “remain in Mexico”, which expels people back to Mexico as their claim to stay in the US is considered. Joe Biden opposed this plan but recently reinstated it following a legal challenge from two states.
This sort of deterrence is unlikely to completely halt people from seeking refuge in the US, particularly those increasingly fleeing intolerable conditions in Mexico and Central America that are being worsened by the climate crisis. A series of droughts and storms have wreaked havoc upon communities, particularly farmers, forcing them to seek livable alternatives further north.
“We knowingly kill them at the border. And yet we ignore them once they’re here, when they’re doing the jobs that Americans don’t want to do,” said Jason De Leon, an anthropologist at the University of California, Los Angeles, who was also involved in the study.
“I think we were about to live in a climatic version of the book Children of Men, where instead of a fertility issue, we’re dealing now with a global climatic issue. We are seeing people having to leave their homes because of climate change,” he added. “And I think that we can no longer disentangle those two things, that they’re intimately related and it’s only going to get worse, unfortunately for a lot of people around the globe.”