Some 53 people — migrants from Mexico, Guatemala, Honduras and El Salvador - were found dead in a baking-hot truck outside San Antonio, Texas late last month.
By the time the truck was discovered, many inside had succumbed to the heat, as temperatures in the area reached around 100 degrees Fahrenheit (38 degrees Celsius).
The San Antonio Fire Chief said the few people who had survived were “hot to the touch”.
It is far from the first tragedy of this nature. At least two previous incidents with dangerously hot trucks have led to migrant deaths in Texas.
As the climate crisis worsens, crossing the southern US border is becoming even more dangerous as travellers face extreme and persistent heat which can lead to life-threatening dehydration, and exposure.
An ever hotter planet is also forcing more and more people to make the trek north as some Latin American countries face worsening droughts and hurricanes.
“The irony is that you’ve got people who are who are fleeing a place like Honduras because of climate change,” Jason De León, an anthropologist at the University of California, Los Angeles tells The Independent.
And when they arrive at the US-Mexico border, he adds, they run right into the impacts of climate change once again.
Research co-authored by Dr De León last year found that between 1998 and 2019, over 7,000 people have been found dead in the border region, with many more deaths likely unreported — often from extreme dehydration as they attempt to cross remote, hot and dry corners of the southwestern desert.
Large parts of the border region have inhospitable conditions. The water-scarce desert stretches along craggy mountain ranges and low, flat valleys, with summer daytime temperatures often rising over 100F (38C).
Such an environment can cause immense pressure from heat and potential dehydration. “Walking in the Sonoran Desert right now, or through South Texas right now — it’s just unbearable,” says Dr De León. “I mean, it is incredibly traumatic on the body.”
The study last year found that an adult travelling between Nogales, Mexico and Three Points, Arizona — about 50 miles as the crow flies — would lose around seven to eight litres of water while making the journey during the day.
Around those two cities, locations where migrants have been found dead were “disproportionately clustered” in areas more likely to lead to dehydration, the researchers found.
Conditions are likely to become more dangerous as the planet warms. The study found that with a moderate level of future warming, the physiological risks of making the journey from Nogales to Three Points would increase by 34 per cent — making it even more dangerous to cross the border on foot.
Migration has also been made more dangerous by immigration policy along the border, Dr De León says.
In the mid-1990s, the US government instituted a policy called “prevention through deterrence” which tried to discourage immigration along the southern border by beefing up security in cities and forcing migrants crossing illegally to traverse more remote, dangerous terrain, he notes.
The point was to make crossing more difficult to discourage people from coming, he adds.
“Basically, we’re weaponizing nature,” Dr De León says.
That policy may have led to a spike in deaths in the border region. Between 1990-1995, Pima County, Arizona recovered an average of eight migrant-related deaths every year. Between 2015-2020, that average had risen to 143.
The policy also hasn’t really worked, according to Dr De León. “People know it’s dangerous now, and they still don’t have a choice and they’re still doing it,” he says. “Except the difference now is that thousands of people have died while crossing through Texas and through Arizona.”
And with the climate crisis, using the desert as a “weapon” is likely to become a lot more deadly. So far, the average temperature in Arizona has risen about 2.5F (1.4C) since the early twentieth century, according to a US government analysis.
By the end of the century, that amount of warming could double — or more, while the region also faces a higher risk of drought and wildfire, the analysis adds.
But environmental factors aren’t solely responsible — governments could also play a role in making the journey less perilous, Hélène Benveniste, a post-doctoral environmental researcher at Harvard University, tells The Independent.
Even with deteriorating environmental conditions, providing things like cool rooms along the way could make routes safer, she said.
In 2018, an activist with the group No More Deaths, which leaves supplies like water along parts of the southern border, was arrested on charges of harbouring migrants, reported the Associated Press. He was acquitted the next year.
But strategies like water distribution can only do so much in the vast and inhospitable desert, Dr De León says. “It’s like putting a Band-Aid on a gunshot wound.”
To really solve the issue, you could stop policies that force people out into the remote desert, he says. And the US government could change the immigration process by reassessing asylum programs and work visas, he adds.
“I think we need to completely reconsider the way in which we allow people to come and go in this country,” Dr De León says.
Legalizing parts of the migration process could open resources that might prevent deaths along the routes, Dr Benveniste said. “Making the migration journey more legal obviously allows for a better involvement of local and national governments in the journey itself.”
In addition to changing the stakes of the journey, the climate crisis is expected to spur global migration as people look to escape disasters like droughts, hurricanes and extreme flooding.
“A lot of the folks who are crossing the US-Mexico border, and who are on the back of that truck, are oftentimes fleeing the impacts of climate change,” Dr De León says.
Many people have left places like western Mexico because of drought, or Honduras because of the devastating hurricanes that hit that country in 2020, he added.
As global temperatures continue to rise, more upheaval is likely to continue.
“The history of our species, our ability to survive as long as we have, has been a fact that we are a mobile species,” says Dr De León. “When our environment becomes difficult and inhospitable, we move to a new place where we can thrive.”
“People are going to keep moving as the climate changes,” he adds. “And we need to be ready for that.”