Spain records temperature of 46C as Europe heatwave continues

 

by 

Danai Nesta Kupemba

BBC News

 

 

A heatwave continues to grip large parts of Europe, with authorities in many countries issuing health warnings amid searing temperatures.

Southern Spain is the worst-affected region, with temperatures in the mid-40s Celsius recorded in Seville and neighbouring areas.

A new heat record for June of 46C was set on Saturday in the town of El Granado, according to Spain's national weather service, which also said this month is on track to be the hottest June on record.

Red heat warnings are in force in parts of Portugal, Italy and Croatia, with numerous amber warnings covering areas of Spain, France, Austria, Belgium, Bosnia & Herzegovina, Hungary, Serbia, Slovenia and Switzerland. 

 

In Barcelona, a woman died after completing a shift as a road sweeper on Saturday, when temperatures were very high. Local authorities are investigating her death.

In Italy, emergency departments across the country have reported an uptick in heatstroke cases, mainly affecting "elderly people, cancer patients, or homeless people", Mario Guarino, vice president of the Italian Society of Emergency Medicine told the AFP news agency.

Hospitals such as the Ospedale dei Colli in Naples have set up dedicated heatstroke pathways to speed up access to vital treatments such as cold water immersion.

The city of Bologna further to the north has set up seven climate shelters with air conditioning and drinking water, while Rome has offered free access to city swimming pools for those over 70.

Tourists cool off under a cloud of mist in Valencia, Spain on Sunday

A pharmacist in Portugal's capital Lisbon told Reuters news agency that, despite telling people "not to go out" during the hottest hours of the day, "we have already had some cases of heat strokes and burns".

The severe heat has also affected countries across the western Balkans where temperatures have reached in excess of 40C.

Serbia registered its highest-ever temperature since it began recording them in the 19th century. In Slovenia, the hottest-ever June temperature was recorded on Saturday.

North Macedonia is also sweltering as temperatures reached 42C on Friday. 

 

More hot weather to come

Some areas will continue to get hotter until the middle of the week, with temperatures rising across France, Germany, Italy and the UK over the next few days.

Yellow and amber alerts are in place for parts of England this weekend, and temperatures in London may reach 35C on Monday.

The heat has been building under a big area of high pressure, with dry air descending and warming.

As that process has continued over a number of days, temperatures have climbed. The area of high pressure will move eastwards over the next few days – taking the high temperatures northwards and eastwards with it.

While it is hard to link individual extreme weather events to climate change, heatwaves are becoming more common and more intense due to climate change.

Scientists at World Weather Attribution, who analyse the influence of climate change on extreme weather events, say June heatwaves with three consecutive days above 28C are about 10 times more likely to occur now compared to pre-industrial times.

Additional reporting by BBC Weather, Guy DeLauney and Guy Hedgecoe

‘Explosive increase’ of ticks that cause meat allergy in US due to climate crisis. Unusually aggressive lone star ticks, common in the south-east, are spreading to areas previously too cold for them

 

A vial of live lone star ticks being displayed. Photograph: Portland Press Herald/Getty Images

by  Oliver Milman

 

Blood-sucking ticks that trigger a bizarre allergy to meat in the people they bite are exploding in number and spreading across the US, to the extent that they could cover the entire eastern half of the country and infect millions of people, experts have warned.

Lone star ticks have taken advantage of rising temperatures by the human-caused climate crisis to expand from their heartland in the south-east US to areas previously too cold for them, in recent years marching as far north as New York and even Maine, as well as pushing westwards.

The ticks are known to be unusually aggressive and can provoke an allergy in bitten people whereby they cannot eat red meat without enduring a severe reaction, such as breaking out in hives and even the risk of heart attacks. The condition, known as alpha-gal syndrome, has proliferated from just a few dozen known cases in 2009 to as many as 450,000 now.

 

“We thought this thing was relatively rare 10 years ago but it’s become more and more common and it’s something I expect to continue to grow very rapidly,” said Brandon Hollingsworth, an expert at the University of South Carolina who has researched the tick’s expansion.

“We’ve seen an explosive increase in these ticks, which is a concern. I imagine alpha-gal will soon include the entire range of the tick, which could become the entire eastern half of the US as there’s not much to stop them. It seems like an oddity now but we could end up with millions of people with an allergy to meat.”

The exact number of alpha-gal cases is unclear due to patchy data collection but it’s likely to be a severe undercount as people may not link their allergic reaction to the tick bites. The Centers for Disease Control and Prevention (CDC) has said around 110,000 cases have been documented since 2010 but acknowledges the true number could be as high as 450,000.

Cases will rise further as the ticks spread, aided by their adaptability to local conditions, according to Laura Harrington, an entomologist and disease specialist at Cornell University. “With their adaptive nature and increasing temperatures, I don’t see many limits to these ticks over time,” she said.

A female lone star tick, or Amblyomma americanum collected in Maryland on 21 Jun 2017. Photograph: BSIP/Universal Images Group/Getty Images

Alpha-gal is a confounding condition because it doesn’t cause an immediate allergic reaction, unlike a peanut allergy, with symptoms often appearing several hours after consuming meat. The syndrome is not caused by a pathogen but spurs an allergy to a sugar molecule found in mammals and an array of other things, from toothpaste to medical equipment. Researchers think the condition can wane over time but is also worsened by further tick bites.

This leads to a confusing and fraught experience for the growing number of Americans with alpha-gal, who are now girding for another expected hot summer full of ticks. “The ticks are rampant this year, I’ve pulled 10 ticks off me this season alone, it feels like they are uncontrollable at the moment,” said Heather O’Bryan, a horticulturist in Roanoke, Virginia, who has alpha-gal. “They are so disgusting. I’m not afraid of a lot, but I’m afraid of ticks.”

In 2019, O’Bryan suffered full body hives and struggled to breathe after eating a pork sausage. “It was terrifying experience, I didn’t know I had an allergy but it almost killed me,” she said. She now avoids products containing mammal-derived elements, such as certain toothpastes and even toilet paper, due to adverse reactions.

Dairy, another mammalian product, is also off limits. “I’ve learned what I can eat now, but I was so sad when I realized I couldn’t have pizza again, I remember crying in front of a frozen pizza in the supermarket aisle,” she said.

There is now an “almost constant” stream of new members to the Facebook alpha-gal support groups that O’Bryan is part of, she said, with her region of Virginia now seemingly saturated by the condition. “Everyone knows someone who has it, I talk a friend off a ledge once a month when they’ve been bitten because they are so afraid they have it and are freaking out,” she said.

Lone star ticks are aggressive and can speedily follow a human target if they detect them. “They will hunt you, they are like a cross between a lentil and a velociraptor,” said Sharon Pitcairn Forsyth, a conservationist who lives in the Washington DC area.

A particular horror is the prospect of brushing up against vegetation containing a massed ball of juvenile lone star ticks, know as a “tick bomb”, that can deliver thousands of tick bites. “They are so tiny you can’t see them but you have to take it seriously or you’ll never get them off you,” said Forsyth, who now carries around a lint roller to remove such clusters.

After being diagnosed with alpha-gal, Forsyth set up online resources about the condition to help spread awareness and advocate for better food labeling to include alpha-gal warnings. “I get calls from doctors asking questions about this because they just don’t know about it,” she said. “I’m not a medical professional, so I just send them the research papers.”

As the climate heats up, due to the burning of fossil fuels, ticks are able to shift to areas that are becoming agreeably warm for them. Growing numbers of deer, which host certain ticks, and sprawling housing development into natural habitats is also causing more interactions with ticks. “Places where houses push up against habitats and parks where nature has regrown are where we are seeing cases,” said Hollingsworth.

But much is still unknown, such as why lone star ticks, which have long been native to the US, suddenly started causing these allergic reactions. Symptoms can also be alarmingly varied – Forsyth said she rarely eats out now because of concerns of contamination in the food and even that alpha-gal could be carried to her airborne, via the steam of cooked meat.

“Some people are scared to leave the house, it’s hard to avoid,” she said. “Many people who get it are over 50, so the first symptom some of them have is a heart attack.”

So how far can alpha-gal spread? Cases have been found in Europe and Australia, although in low numbers, while in the US it’s assumed lone star ticks won’t be able to shift west of the Rocky mountains. But other tick species might also be able to spread alpha-gal syndrome – a recent scientific paper found the western black legged tick and the black legged tick, also called the deer tick, could also cause the condition.

Hanna Oltean, an epidemiologist at Washington state department of health, said it was “very surprising” to find a case of alpha-gal in Washington state from a person bitten by a tick locally, suggesting the western black legged tick could be a culprit.

“The range is spreading and emerging in new areas so the risk is increasing over time,” Oltean said. “Washington state is very far from the range and the risk remains very low here. But we don’t know enough about the biology of how ticks spread the syndrome.”

The spread of alpha-gal comes amid a barrage of disease threats from different ticks that are fanning out across a rapidly warming US. Powassan virus, which can kill people via an inflammation of the brain, is still rare but is growing, as is Babesia, a parasite that causes severe illnesses. Lyme disease, long a feature of the US north-east, is also burgeoning.

“We are dealing with a lot of serious tick-borne illnesses and discovering new ones all the time,” said Harrington.

“There’s a tremendous urgency to confront this with new therapies but the problem is we are going backwards in terms of funding and support in the US. There have been cuts to the CDC and NIH (National Institutes of Health) which means there is decreasing support. It’s a major concern.”

 

The World Is Warming Up. And It’s Happening Faster. Human-caused global warming has been increasing faster and faster since the 1970s.

 

Relative to the average temperature between 1951 and 1980.

 

By Sachi Kitajima MulkeyClaire Brown and Mira Rojanasakul

 

Summer started barely a week ago, and already the United States has been smothered in a record-breaking “heat dome.” Alaska saw its first-ever heat advisory this month. And all of this comes on the heels of 2024, the hottest calendar year in recorded history.

The world is getting hotter, faster. A report published last week found that human-caused global warming is now increasing by 0.27 degrees Celsius per decade. That rate was recorded at 0.2 degrees in the 1970s, and has been growing since.

This doesn’t surprise scientists who have been crunching the numbers. For years, measurements have followed predictions that the rate of warming in the atmosphere would speed up. But now, patterns that have been evident in charts and graphs are starting to become a bigger part of people’s daily lives.

“Each additional fractional degree of warming brings about a relatively larger increase in atmospheric extremes, like extreme downpours and severe droughts and wildfires,” said Daniel Swain, a climate scientist at the University of California.

 

While this aligns with scientific predictions of how climate change can intensify such events, the increase in severity may feel sudden to people who experience them.

“Back when we had lesser levels of warming, that relationship was a little bit less dramatic,” Dr. Swain said. “There is growing evidence that the most extreme extremes probably will increase faster and to a greater extent than we used to think was the case,” he added.

 Take rainfall, for example. Generally, extreme rainfall is intensifying at a rate of 7 percent with each degree Celsius of atmospheric warming. But recent studies indicate that so-called record-shattering events are increasing at double that rate, Dr. Swain said.

A construction worker in Washington, D.C., on Tuesday during this week’s heat wave. Credit...Wesley Lapointe for The New York Times

 

 “There is no weather that’s happening outside of climate,” said Kate Marvel, a climate scientist and author of the book “Human Nature.”

 

 

“This is stuff that’s manifesting in the real world,” she said, citing catastrophes like Hurricane Helene and Vermont’s historic floods in 2023.

According to Dr. Swain, scientists have yet to come to a universal understanding of these events, in part because the infrequent nature of outliers makes them difficult to study.

And as warming has intensified, so have the impacts on vulnerable regions of the planet like the Arctic and Antarctic, making previously rare or hidden consequences more apparent. Scientists are fine-tuning their models to understand the behavior of the vast ice sheets in such places to match the rapid changes they’re observing.

In March, a NASA analysis found that sea levels had risen faster than expected in 2024, in part because of a combination of melting glaciers and heat penetrating deeper into oceans, causing them to expand thermodynamically. Sea surface temperatures are rising faster than previously predicted, too, according to a study published in April by researchers at the National Center for Earth Observation in Britain.

Cecilia Bitz, a professor of climate science at the University of Washington, said that modeling the Earth is complex, and that there are an innumerable amount of small factors that could be taken into account. But even with these uncertainties, scientists have ways of building their models to identify trends that are largely accurate. “Nothing is defying our big picture about the physics of the climate system,” Dr. Bitz said.

 

Overall atmospheric warming has consistently followed modeling predictions for decades. But recently, the fundamental imbalance responsible for this heat has been tilting — catching even scientists off guard.

Global warming is a symptom of Earth’s energy imbalance, which is a measure of the difference between the total amount of heat reaching Earth from the sun, and the amount radiating back into space.

In May, a paper analyzing data from a NASA satellite found that this imbalance had grown faster than expected, more than doubling in the past two decades and becoming nearly twice as large as it was previously predicted to be.

Zeke Hausfather, a research scientist at Berkeley Earth, said climate scientists were still working to understand these findings. There are various theories, such as fewer emissions of aerosols, a type of air pollution that is harmful to human health and that increases the reflectivity of clouds, which bounce the sun’s heat back into space.

Historically, aerosol emissions have masked the warming effect of greenhouse gases like carbon dioxide. Over the past half-century or so, as nations reduced certain kinds of air pollution, aerosol emissions fell significantly. According to Dr. Hausfather, this change is the primary reason atmospheric warming has accelerated in recent decades.

 

But the most worrying possibility behind Earth’s energy imbalance, he said, is how the general nature of clouds may be changing in response to climbing temperatures. It’s a feedback loop that could potentially exacerbate warming and is “one of the single biggest uncertainties in predicting future climate,” he said.

As the world continues to emit planet-warming greenhouse gasses, and temperatures climb past what the human world was built to handle, Dr. Marvel said, more people will experience climate change in damaging and frightening ways.

“It’s always worse than expected when it happens to you,” Dr. Marvel said. “It is one thing to see something in a climate model, and it’s a totally different thing to actually experience it in your own life.”

 

 

More than 150 fall ill from extreme heat at New Jersey graduations. A ‘mass casualty incident’ as temperatures soar to upper 90s fahrenheit in the region

Hinchliffe Stadium in Paterson, New Jersey. Photograph: Bruce Bennett/Getty Images

 by Edward Helmore

More than 150 people fell ill with heat at an outdoor high school graduation ceremony in New Jersey on Monday – and the fire chief of the city of Paterson declared “a mass casualty incident” due to the overwhelming number of those who needed emergency treatment.

The incident happened as students from several local schools in the city gathered at Hinchliffe Stadium to hear their names read out as graduates. Paterson’s fire department said about 50 people were evaluated, and nine were sent to a local hospital from the stadium.

During a second ceremony at the stadium, about 100 people ended up needing treatment – and seven were hospitalized. The Paterson mayor, André Sayegh, declared a state of emergency due to the high heat and canceled all recreational activities “until further notice”.

 

Temperatures in the region have soared in recent days, registering in the upper 90s fahrenheit. But the humidity pushes heat indexes to 107F (42C). In all, 150 million people have been under heat alerts from Maine to eastern Texas.

The brutal temperatures stem from a so-called heat dome, which is when high pressure from Earth’s atmosphere compresses warm air and pushes it down to the surface. They have been increasingly common in the US in recent years because of rising global temperatures being spurred by Earth’s ongoing climate emergency.

Temperatures in New York City on Tuesday inspired the attorney general, Letitia James, to predict that the heat could benefit the progressive candidate Zohran Mamdani, who is running in the Big Apple’s closely watched Democratic mayoral primary.

“Mother Nature will have the last word,” James said. Taking an overt dig at Mamdani’s rival Andrew Cuomo, who resigned as New York governor amid accusations of sexually harassing women, James added: “She represents women scorned.

“How ironic.”

In the north-eastern US, several heat records look set to fall as temperatures in some locations are predicted to reach 110F. “Significant and dangerous heat continues today, with potentially some of the hottest temperatures in over a decade in some locations,” the weather service Accuweather said on Tuesday.

The national Storm Prediction Center says all areas of New Jersey have a “marginal” risk of seeing severe thunderstorms with small hail and damaging winds on Wednesday. That could bring a reprieve from the temperatures while giving residents other weather perils to worry about.

 

 

Tens of millions in US face dangerously hot weather in rare June heatwave. Much of country from Minnesota to Maine under heat advisory as temperatures expected to pass 100F this week

Man uses a portable fan as he tries to stay cool in Busch Stadium before a baseball game between the St Louis Cardinals and the Cincinnati Reds on Saturday. Photograph: Jeff Roberson/AP

 Associated Press

 Tens of millions of people across the midwest and east braced on Sunday for another sweltering day of dangerously hot temperatures as a rare June heatwave continued to grip parts of the US.

Most of the north-eastern quadrant of the country from Minnesota to Maine was under some type of heat advisory on Sunday. So were parts of Arkansas, Tennessee, Louisiana and Mississippi.

The temperature had already reached 80F (26.6C) in the Chicago area by 7.30am on Sunday, according to the National Weather Service. Forecasts called for heat indices of between 100 and 105F.

The heat index in Pittsburgh was expected to top 105F. The temperature in Columbus, Ohio, was 77F at 8.30am. Highs there were expected to reach 97F with a heat index around 104F.

 

Forecasts called for a heat index of 100F in Philadelphia on Sunday, with a 108F heat index on Monday.

The city’s public health department declared a heat emergency starting at noon on Sunday and ending on Wednesday evening. Officials directed residents to air-conditioned libraries, community centers and other locations, and set up a “heat line” staffed by medical professionals to discuss conditions and illnesses made worse by the heat. At Lincoln Financial Field, officials said each fan attending Sunday’s Fifa World Cup match would be allowed to bring in one 20oz plastic bottle of water.

Forecasters warned the heat index in Cromwell, Connecticut, would reach 105F on Sunday, which could make life brutal for golfers Tommy Fleetwood and Keegan Bradley as they compete during the final round of the Travelers Championship.

Elly De La Cruz, a Cincinnati Reds shortstop playing against the Cardinals in St Louis, and Trent Thornton, a Seattle Mariners reliever facing the Cubs in Chicago, got sick on Saturday while playing in the extreme heat.

 

Sunday marked the second straight day of extreme heat across the midwest and east coast. Heat indices on Saturday hit 103F in Chicago and 101F in Madison, Wisconsin, turning that city’s annual naked bike ride into a sticky and sweaty affair.

Lynn Watkins, 53, is the director of Sacred Hearts daycare in Sun Prairie, a Madison suburb. She said that she tried to sit outside on Saturday to grill but it was so hot she had to go inside. She plans to cancel all outdoor activities at the daycare on Monday with highs around 93F forecast.

“I can’t stand being outside when it’s like this,” she said. “I just want to sit in my air conditioning.”

Minneapolis baked under a heat index of 106F. The actual temperature was 96F, which broke the previous record for the date of 95F set in 1910, according to the weather service.

 

The heat is expected to persist into the coming week, with the hottest temperatures shifting eastward. New York City is expected to see highs around 95F on Monday and Tuesday. Boston is on track for highs approaching 100F on Tuesday, and temperatures in Washington DC were expected to hit 100F on Tuesday and Wednesday.

Meteorologists say a phenomenon known as a heat dome, a large area of high pressure in the upper atmosphere that traps heat and humidity, is responsible for the extreme temperatures.

Mark Gehring, a National Weather Service meteorologist in Sullivan, Wisconsin, said this level of heat is not uncommon during the summer months in the US, although it usually takes hold in mid-July or early August. The most unusual facet of this heatwave is the sheer amount of territory sweltering under it, he said.

“It’s basically everywhere east of the Rockies,” he said, referring to the Rocky Mountains. “That is unusual, to have this massive area of high dewpoints and heat.”

 

 

Deadly weekend heat in England ‘100 times more likely’ due to climate crisis. High temperatures likely to cause deaths and will worsen in future as global heating intensifies, scientists warn

Researchers say the 32C expected this weekend in the south-east would have been expected only once every 2,500 years without the climate crisis. Photograph: Martin Godwin/The Guardian

 Damian Carrington

The dangerous 32C heat that will be endured by people in the south-east of England on Saturday will have been made 100 times more likely by the climate crisis, scientists have calculated.

Global heating, caused by the burning of fossil fuels, is making every heatwave more likely and more intense. The 32C (89.6F) day forecast on Saturday would have been expected only once every 2,500 years without the climate crisis, the researchers said, and June heatwaves are now about 2-4C (3.6-7.2F) hotter than in the past.

 

The heat is expected to cause premature deaths, particularly among older and vulnerable people. More than 10,000 people died before their time in summer heatwaves between 2020 and 2024, according to the UK Health Security Agency, and the UK government has been heavily criticised for failing to properly prepare people for extreme weather.

Prolonged heat is especially dangerous as it gives no time for people’s bodies to cool off. Maximum temperatures in the south-east are expected to be above 28C for three consecutive days. The scientists said this heatwave was made 10 times more likely by the climate crisis.

Dr Ben Clarke at Imperial College London, who was part of the research team, said the culprit for the extreme heat was clear. “This weather just wouldn’t have been a heatwave without human-induced warming,” he said.

Climate breakdown drove the annual global temperature in 2024 to a new record and carbon dioxide emissions from coal, oil and gas are still rising. If that continues for just two more years, passing the internationally agreed limit of 1.5C above preindustrial levels will be inevitable, intensifying the extreme weather already taking lives in the UK and across the globe.

Clarke said: “With every fraction of a degree of warming, the UK will experience hotter, more dangerous heatwaves. That means more heat deaths, more pressure on the NHS, more transport disruptions, and tougher work conditions. The best way to avoid a future of relentless heat is by shifting to renewable energy.”

Dr Friederike Otto, also at Imperial College London, said: “It is really important to highlight this early summer heatwave because the impacts of heat are still severely underestimated, and the UK is not prepared for this type of weather.” The Climate Change Committee, the government’s official advisers, said in April that the UK’s preparations for adapting to a changing climate were “inadequate, piecemeal and disjointed”.

Otto said: “Heatwaves are called the silent killer, because we don’t see people dropping dead on the street, but killers they are. In Europe in 2022, more than 60,000 people died in the summer from extreme heat.”

Maja Vahlberg at the Red Cross Red Crescent Climate Centre said: “Sadly most people die from heat indoors and alone, especially older people and those with underlying health conditions, such as lung or heart disease.”

Prof Mike Tipton, a physiologist at Portsmouth University, said: “The human body is not designed to tolerate prolonged exposure to this sort of extreme heat. It is undeniable that climate change is now costing British lives. Those politicians and commentators who pour scorn on climate action should reflect on this fact because, until we stop emitting greenhouse gases, these episodes are only likely to become more extreme.”

The extremely dry spring, combined with soaring temperatures, means the UK is also facing a high risk of wildfires, said Theodore Keeping, also at Imperial College London: “We’ve already seen the highest burnt area on record in the UK this year.” People should take extreme care with fires, barbecues and cigarettes, he said.

 

The rapid study of the role of global heating in the predicted weekend heatwave compared the likelihood of the high temperatures in today’s hotter climate with that in the cooler preindustrial period. The team, part of the World Weather Attribution group, was also able to reuse detailed climate modelling undertaken for a similar heatwave in 2022, speeding up their conclusions.

They said older people were at greatest risk from the high temperatures, but that others with existing vulnerabilities could also be affected, with the effectiveness of some medications being changed by the heat or affecting people’s ability to cool down.

Sweating is how the body cools so it is vital to drink plenty of water, the researchers said. Closing windows and curtains during the day and opening them in the cool of the night can help keep temperatures in homes down, they said. A recent study estimated that 80% of UK homes overheat in the summer.

Temperatures in the UK rose above 40C for the first time in 2022. The Met Office said on Wednesday that the UK had a 50/50 chance of temperatures soaring to 40C again in the next 12 years as the climate crisis worsens and that 45C could not be ruled out.

Extreme heat is more deadly than floods, earthquakes and hurricanes combined, according to a report by the insurance giant Swiss Re published on 12 June. “Up to half a million people globally succumb to the effects of extreme heat each year,” it said.

“Extreme heat used to be considered the ‘invisible peril’ because the impacts are not as obvious as of other natural perils,” said Jérôme Haegeli, chief economist at Swiss Re. “With a clear trend to longer, hotter heatwaves, it is important we shine a light on the true cost to human life, our economy, infrastructure, agriculture and healthcare.”

 

 

Climate crisis could hit yields of key crops even if farmers adapt, study finds. Production of staple crops projected to fall by as much as 120 calories per person per day for every 1C of heating

 

Maize was one of the staple crops covered by the study. Photograph: Maksim Safaniuk/Shutterstock

by  Ajit Niranjan

 

Some of our critical staple crops could suffer “substantial” production losses due to climate breakdown, a study has found, even if farmers adapt to worsening weather.

Maize, soy, rice, wheat, cassava and sorghum yields are projected to fall by as much as 120 calories per person per day for every 1C the planet heats up, according to new research in Nature, with average daily losses that could add up to the equivalent of not having breakfast.

The study found rising incomes and changes in farming practices could stem the losses by about a quarter by 2050 and by one-third by 2100 – though they would not stop them entirely.

 

“In a high-warming future, we’re still seeing caloric productivity losses in the order of 25% at global scale,” said Andrew Hultgren, an environmental economist at the University of Illinois Urbana-Champaign and lead author of the study. “It’s not as bad as a future where adaptation doesn’t happen at all, but it’s not this rosy ‘agriculture is going to benefit from climate change’ kind of picture.”

Farmers are among those hardest-hit by extreme weather events, but scientists have struggled to quantify what climate breakdown will do to food production. A major source of uncertainty is the extent to which farmers will adapt to hotter temperatures by changing which crops they use, when they plant and harvest them, and how they grow them.

The team of researchers from the US and China used data from 12,658 regions in 54 countries to capture the extent to which food producers have adapted to different changes in the climate. They applied these historical relations to models simulating future crop production as temperatures rise and economies grow, and compared the losses with a hypothetical world in which global heating stopped in the early 2000s.

 

In an extreme heating scenario, the study found, the relative yield for a crop such as soy would fall by 26% by 2100, even after accounting for adaptation, rising incomes and the effect of plants growing faster due to extra carbon dioxide in the atmosphere.

A more realistic heating scenario – closer to the level that current policies will cause – would lead to yield losses of 16% for soy, 7.7% for wheat and 8.3% for corn, the study found. Rice was the only one of the six crops the researchers studied whose yields would rise because of climate change, with an expected gain of 4.9%.

The global population is projected to rise from about 8 billion today to 10 billion by the end of the century, increasing demand for food as carbon pollution warps weather patterns. The researchers found the greatest losses would hit modern-day “bread basket” regions with highly productive lands, but added that people in poorer countries would be among the ones least able to afford food.

“In a lot of climate impact studies, the global poor get hurt, and that’s true here too,” said Hultgren. “What is different from a lot of the previous work out there is that relatively rich, well-to-do portions of the world that are bread baskets are actually hit the hardest.”

The research, which uses econometric methods to gauge the total effect of adapting, contrasts with previous studies that explicitly model biophysical interactions. A study in Nature Communications in 2022 using the latter approach found timely adaptation of growing periods would increase actual crop yields by 12%.

 

Jonas Jägermeyr, a researcher at Columbia Climate School and co-author of the study, said the new research did not cover adaptation options that are not implemented today and that its results were likely to be pessimistic.

“Empirical impact studies are known to be overly pessimistic when it comes to far-into-the-future scenarios,” he said. “Process-based models show the importance of plant growth interactions that cannot be empirically trained on historical data.”

But such models have also been criticised for exploring what is theoretically possible without reflecting real-world constraints, such as market failures, human error and the availability of funds.

“The findings [of the new study] are reasonable but represent one end of a legitimate scientific debate,” said Ehsan Eyshi Rezaei, a crop scientist at the Leibniz Centre for Agricultural Landscape Research.

He added: “I view these results as a valuable empirical reality check showing we cannot assume perfect adaptation will save us – even if the truth likely lies between their pessimistic projections and [other researchers’] optimistic ones.”