Tag: climate

After the Election, California (Yes, That Hellscape) Will Keep Moving the World Forward No Matter What

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Just take the area of gasoline-powered transportation. After World War II, when American car culture was famously getting minted in Southern California, the state used a gas tax hike to build out one of the first modern freeway networks. In the ’50s, the US federal government borrowed that same model to construct the interstate highway system. Then, starting in the 1980s, California led the fight against leaded gasoline, eventually banning its sale in 1992, four years before the US as a whole did the same. In 2019, after Donald Trump’s administration rolled back emissions standards for cars, California struck a deal with the world’s leading carmakers, from Ford to Honda to VW and BMW—to make existing standards even tougher in the face of climate change. The size of the California market made this a de facto national standard (which the Biden administration later ratified).

It would be one thing if this were just a history lesson. But the same kind of dynamic is playing out right now in a few crucial arenas that virtually no one beyond California is talking about. And I’m happy to report that the America taking shape on its Pacific coast is again inventing solutions far more rapidly than conventional wisdom has accounted for.

I was bullish on these emerging transformations even before Kamala Harris became the Democratic nominee for president. If she wins, what she knows from California will presumably affect her approach to the country and the world. Her California-ness is one of the least-discussed but most important aspects of her, including the upbeat approach to today’s diversity and tomorrow’s opportunities that is such a contrast to Donald Trump.

But if she doesn’t get that far, California is likely to chug along with all the more purpose, maintaining its nation-scale example of how else things can be done. Whoever guides national politics, California deserves new attention as the “reinvention state” rather than a “resistance state.” Even under Trump, there’s still a good chance that as California goes, so eventually goes the country, and eventually much of the world. Here are a few illustrations of where it’s headed. None of these is “the” solution to California’s many problems. But each of them illustrates the creative spirit from which solutions have always come.

Train to Somewhere

For starters, let’s return to the thread of transportation: By now, of course, the pioneering freeway system California built in the 20th century is a maxed-out, congested mess. And the state cannot build more freeways; where they’re needed, there’s no more room, and any that are built fill up as soon as they’re opened. Without new forms of transportation, the state will become increasingly paralyzed, and all its other problems will become worse. Which is why, back in 2008, California voters approved a nearly $10 billion initial bond issue to build a high-speed rail line eventually running some 500 miles from Los Angeles to San Francisco, through the Central Valley corridor. That was 16 years ago. If you’ve heard anything at all about this project since then, it’s that it is a white elephant, a doomed relic, a cautionary lesson, and any other metaphor for failure you might choose.

And yes, the complaint list is long. The project is way over budget (to the tune of $100 billion) and far behind its original schedule. Parts of the line were supposed to be up and running already. As it is, the first service isn’t projected to begin until 2030—and then only on the 171-mile segment from Merced, in the northern half of California’s Central Valley, to Bakersfield, on the southern end. This abbreviated initial route has been dubbed a “train to nowhere,” a stock insult that grates on people in the Central Valley but captures the frustration of people stuck in LA or Bay Area traffic. And given how the entire funding-hungry project has become an object of the culture wars, it is little wonder that for many, the project seems as remote and implausible as human settlements on Mars.

But I’ve been following the back-and-forth for more than a decade, and I’ve started to see California’s high-speed rail project with a new clarity. In the aviation world, pilots are trained to recognize the “point of no return,” when you’ve gone so far that you’d only lose by going back. That’s where California is with high-speed rail. Consider the weight of a few recent facts: This summer the project received full “environmental clearance” for the entire 463 miles from downtown LA to downtown San Francisco, with clearance for a further 31 miles from LA to Anaheim expected next year. Nearly all of the thousands of necessary land parcels have been secured. Construction in the Central Valley is much further along than most people realize: Some 12,000 people have long been at work there, and test trains should be running in three or four years. And what hasn’t sunk in is that, when done, this will be among the very fastest mainline high-speed rail systems running anywhere on Earth. (At 220 mph, it would beat the 200-mph range for European trains and the famed Shinkansen in Japan, or match the fastest stretches of the Beijing-to-Shanghai line in China.) Not only that, in a worldwide first, California’s system will use solar-generated electricity the entire way.

Over the past decade, I’ve visited Fresno, the biggest city along the initial route (population 545,000), about a dozen times. There and in surrounding areas you can see the rail taking shape month by month, mile by mile. You see the kind of gigantic, heavy-industrial construction projects I remember from living in China, when a new subway line seemed to be opening every month. You see earth movers bigger than school buses; concrete bridge-supports as long as airliners.

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October 31, 2024
In Praise of Climate Virtue Signaling

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These changes are real, and very significant, so it’s no wonder that some of the MPs Westlake interviewed said they’re more interested in reducing emissions through technological progress than behavior change. But emissions from things like diet, aviation, and our homes are proving more stubborn—and these are areas where behavior change can play a much bigger role.

Westlake asked the MPs what they thought about advocating for low-carbon behaviors. Two MPs told him that they felt it’d be seen as “virtue signaling,” and when they were asked about cutting their own emissions, some seemed concerned that they’d be seen as environmental radicals. “I think to try to set some sort of example but not be too saintly” is how one MP put it.

That anonymous MP is articulating something I think a lot of people feel on an intuitive level. We compare our behavior to people around us—or people in public life—and feel judged if our own behavior doesn’t match up. If my neighbor has solar panels and I don’t, well, they must think that I just don’t care enough about the environment, right? Faced with these awkward moral questions, it’s easier for MPs—and all kinds of leaders—to preach about the things we can do to reduce emissions that don’t require any moral calculations about our behavior.

But this misses something really major. Decisions around climate change and our individual behavior do have a moral component. It’s not to say that if someone takes an extra flight each year it makes them a bad person, but our moral obligations to other people, and to future people, should be at least part of the decisionmaking calculus. Westlake says this serves an important purpose—not to chastise people for going on holiday, but to direct attention to people whose lifestyles really do have an exceptionally high carbon impact.

I think about this dynamic a lot when it comes to food, and particularly alternatives to beef, which has an outsized carbon footprint compared with almost any other foodstuff. A lot of people hope that making plant-based burgers cheap and tasty will be enough to switch vast numbers of meat-eaters over to the plant-based side. When I hang out at alternative protein conferences, no one wants to talk about the morals of eating meat, although I suspect that is a major motivator for many of the people there. They assume that argument won’t win over any converts to pea protein burgers or whatever.

Maybe they’re right. But I suspect that if we ignore the moral component of climate decisions, we drastically limit the whole scope of our climate ambition. It’s not that morals should make up the whole or even a significant part of our decisionmaking, and we shouldn’t expect people to be morally consistent either. Morality isn’t the whole part of the climate story, but it’s not exactly a footnote either.

“The decisionmaking process of ‘Are you going to take that flight?’ needs to be normalized,” says Westlake. “It doesn’t mean you stop doing everything, but it does mean you make decisions on a consideration of the climate impacts.” And that is part of the reason why leaders—in Westlake’s estimation—really do matter. It matters when Taylor Swift endorses Kamala Harris, and it matters when Taylor Swift takes a short hop in a private jet. If you accept that we should all be thinking about behavior in terms of climate change, then it follows that some people should be paying much more attention than others.

And this gets back to MPs’ wariness about encouraging behavior change. One of the MPs Westlake spoke to was reluctant to discourage flying, saying that it wasn’t fair to stop families from having one foreign holiday per year. When behavior change comes up in the press it’s often framed in absolute terms—stop eating meat, stop flying, stop driving—and so on. But by dismissing behavior change altogether we lose the ability to focus on the wealthy outliers who shoulder what Westlake calls a “differential responsibility” for addressing climate change. Rather than cringing at the prospect of behavior change, perhaps those in charge should focus their attention on their fellow leaders.

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September 23, 2024
Earth got even hotter than we thought during past 500 million years

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Illustration of pterosaurs over a Cretaceous landscape, in a time when Earth was warmer than today

MasPix / Alamy

During the past 500 million years – the time when animals and land plants evolved – the average surface temperature of the planet varied more widely and got even hotter than previously thought.

The mean global surface temperature over this time was 24°C (75°F) and sometimes reached 36°C (97°F), compared with around 14°C or 15°C (57-59°F) at present. The lowest it got was around 11°C (52°F) according to the most rigorous study so far.

“Our research suggests that temperatures during greenhouse intervals [when CO2 levels are high] can get warmer than is indicated by previous [studies],” says Emily Judd of the Smithsonian National Museum of Natural History in Washington DC.

In fact, during the hottest periods, average surface temperatures in the tropics reached 42°C (108°F), according to the study, meaning some land areas could have been too hot for plants and animals to survive. Even polar regions were warm during these times, with average temperatures exceeding 20°C (68°F).

“There were likely a few times over the last half billion years where certain regions were uninhabitable, or where the biodiversity in those regions was extremely low,” Judd says.

Her team also found a stronger link between carbon dioxide levels in the atmosphere and average global temperature than expected. Over such a long time span, the team had expected the relationship to be weaker because of other factors, such as the sun getting brighter.

“This was surprising,” Judd says. “It implies that atmospheric carbon dioxide concentrations play an even bigger role in regulating Earth’s climate than previously thought.”

Experts have long known that for most of the past 500 million years – a stretch known as the Phanerozoic Eon – Earth was hotter than present, with no large ice sheets. But exactly how warm was it?

The ratio of oxygen isotopes in some fossil shells can indicate past ocean temperature, but these are specific to just one part of the ocean. Climate models give a global overview, but because there is so much uncertainty about conditions in the distant past, models might diverge widely from reality.

So Judd and her colleagues combined the two. They ran hundreds of simulations with different starting conditions and assumptions and then picked the model runs that best matched the isotope data to calculate the average global surface temperature at specific times.

Because of their complexity, the models could only run simulations of a few thousand years at intervals of 5 million years, says team member Paul Valdes at the University of Bristol in the UK. “These are snapshot simulations,” he says. “It’s just impossible to run it time-continuous.”

This approach of combining measurements and models, known as data assimilation, is widely used in weather forecasting but had not been systematically applied to the climate over the past 500 million years before.

“This is beautiful work,” says Appy Sluijs at Utrecht University in the Netherlands. “It is the most complete record and best-organised attempt to get to a global mean temperature curve for the Phanerozoic.”

But this approach assumes the isotope temperature data is accurate and the models are right about the temperature of regions for which there is no data, Sluijs says. Such assumptions are not always correct, he says.

So these results are far from the final word on the Phanerozoic. But they do provide a foundation for further improvements, says Terry Isson at the University of Waikato in New Zealand.

“Refining estimates of surface temperatures during the Phanerozoic and also earlier in Earth’s history is critical for deepening our understanding of the co-evolution of life and its environment, and how the Earth’s climate system truly operates,” Isson says.

The fact that it was so much hotter at times in the past than in the present does not mean there is any less reason to worry about human-caused global warming, says Judd. What matters most is the rate of change.

Periods of rapid climate change in the past have led to mass extinctions because organisms couldn’t keep pace, she says. And the current rate of warming is even faster.

“Humans evolved to tolerate colder conditions and have established their populations close to water sources and often near sea level,” she says. “We are faced with challenges such as dwindling water resources, more frequent and intense storms, rising sea levels, and, ultimately, a reduction in habitable and arable land.”

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September 19, 2024
The Outrageous Scheme to Capture and Sell Greenland’s Meltwater

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Fresh water is becoming increasingly scarce in many countries, but not in Greenland. Its ice sheet contains around 6.5 percent of the world’s fresh water, and over 350 trillion liters are estimated to run into the ocean annually. And with climate change accelerating Arctic melting, more and more of Greenland’s water is set to flow off the island every year.

In some places facing water shortages, those very same water molecules are potentially being taken from the sea and turned back into fresh water using desalination, at large electrical and financial cost. This has inspired a startup to pursue an unusual and ambitious business venture that has been partially approved by the Greenland government—harvesting glacier meltwater and shipping it abroad.

“We have one of the world’s finest resources in this area and plenty of it, and we want to push that message out to investors and potential markets,” says Naaja H. Nathanielsen, Greenland’s minister for business and trade.

The startup behind the idea, Arctic Water Bank, plans to build a dam in South Greenland, capture meltwater, and then transport it around the world by boat in bulk water carriers. If all goes according to plan, the company says the project will be completely carbon-neutral and inflict minimal damage to the local environment.

“This is some of the cleanest water in the world. Anyone who has tried Greenlandic water knows that it’s pure, white gold,” says Samir Ben Tabib, cofounder and head of international relations at the startup.

Arctic Water Bank is first and foremost, Ben Tabib stresses, a business, but he believes it could also provide a service to Greenlanders and the wider world. He argues that his company will help the people of Greenland by leveraging the country’s natural resources and paying taxes on income generated from them, and it’s an ambition the government shares. “The goal is twofold,” says Nathanielsen. “It is about new sources of income for the national treasury, and local business development and the associated creation of jobs.”

In the long run, Ben Tabib says, Arctic Water Bank might even help mitigate the impending global water crisis. “It’s probably not something our little business can solve alone, but in Greenland, fresh water is a resource that is just washing into the sea.”

Right now, the startup has the initial permissions it needs. In documents seen by WIRED, the government grants the company sole rights for the next 20 years to use all water and ice from a river near the town of Narsaq. On average, this river produces 21.3 billion liters of water each year, almost entirely meltwater from the Greenland ice sheet. But before any water can be shipped, a dam must be built, and Arctic Water Bank will need an Environmental Impact Assessment (EIA) to be completed to get started on construction.

This isn’t as great a hurdle as it might seem. Greenland may be one of the most untouched environments in the world—roughly the size of Western Europe and home to fewer than 60,000 people—but the construction of dams is not unheard of, says Karl Zinglersen, head of the Department of Environment and Minerals at the Greenland Institute of Natural Resources. In the early 1990s, the first hydroelectric dam was built to serve the capital of Nuuk, and since then, a handful of smaller hydroelectric dams have been built around the country. The EIA process is very thorough, says Zingerlsen, but in his experience it rarely if ever stops a project.

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September 19, 2024
The Green Economy Is Hungry for Copper—and People Are Stealing, Fighting, and Dying to Feed It

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Moqadi Mokoena had been feeling uneasy all day. When he’d left his home on the outskirts of Johannesburg, South Africa, for his job as a security guard, he’d had to turn around twice, having forgotten first his watch and then his cigarettes. He had reason to be nervous. His supervisor had assigned him to join a squad protecting an electrical substation where, just two days earlier, four other guards had been stripped naked and beaten with pipes by gun-wielding thieves. Now, on this day in May of 2021, Mokoena and a fellow guard were at that substation, peering tensely through their truck’s windshield as a group of armed men approached.

Mokoena pulled out his phone and called his wife, the mother of their 1-year-old daughter. He told her about the gang coming toward him. “I’m feeling scared,” he said. He didn’t have a gun himself. “I think they are the same ones who attacked our colleagues.”

“Call your supervisor!” she told him.

Minutes later, the men opened fire with at least one automatic weapon. Mokoena’s partner jumped out of the vehicle but was cut down by bullets. A third nearby guard dove for cover, shot back at the thieves, then ran for help. When he returned with the supervisor, they found Mokoena and his partner dead. Police later said the criminals made off with about $1,600 worth of copper cable.

“We face these dangers every day,” the surviving guard later told a local journalist. “You don’t know if you’ll return home when you leave for duty.”

In most places, power companies are a pretty dull business. But in South Africa they are under a literal assault, targeted by heavily armed gangs that have crippled the nation’s energy infrastructure and claimed an ever-growing number of lives. Practically every day, homes across the country are plunged into darkness, train lines shut down, water supplies cut off, and hospitals forced to close, all because thieves are targeting the material that carries electricity: copper.

The battle cry of energy transition advocates is “Electrify everything.” Meaning: Let’s power cars, heating systems, industrial plants, and every other type of machine with electricity rather than fossil fuels. To do that, we need copper—and lots of it. Second to silver, a rarer and far more expensive metal, copper is the best natural electrical conductor on Earth. We need it for solar panels, wind turbines, and electric vehicles. (A typical EV contains as much as 175 pounds of copper.) We need it for the giant batteries that will provide power when the sun isn’t shining and the wind isn’t blowing. We need it to massively expand and upgrade the countless miles of power cables that undergird the energy grid in practically every country. In the United States, the capacity of the electric grid will have to grow as much as threefold to meet the expected demand.

A recent report from S&P Global predicts that the amount of copper we’ll need over the next 25 years will add up to more than the human race has consumed in its entire history. “The world has never produced anywhere close to this much copper in such a short time frame,” the report notes. The world might not be up to the challenge. Analysts predict supplies will fall short by millions of tons in the coming years. No wonder Goldman Sachs has declared “no decarbonization without copper” and called copper “the new oil.”

As the energy transition gathers speed, the value of copper has also soared. In the past four years, the price of a ton of copper has shot from about $6,400 to more than $9,000. That, in turn, has made electrical wiring, equipment, and even raw metal fresh from the mines into juicy targets for thieves. All around the world, hundreds of millions of dollars’ worth of the metal has been stolen—and countless lives have been lost. With the possible exception of gold, no other metal has caused so much death and destruction.

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August 22, 2024
Elon Musk Is No Climate Hero

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WIRED has been writing about Elon Musk—he of the electric cars, space rockets, tunnel-boring machines, implantable brain interfaces, Mars mission, and internet shitposting—for a long time. He’s always been unpredictable. And yet the most shocking part of his two-hour interview with Republican presidential nominee Donald Trump, broadcast live on X earlier this week, may just have been what Musk didn’t say.

It happened around the 50-minute mark, during a very Trumpian discussion of gas and electricity prices. They were up nationally, Trump said, but “when that comes down and [sic] we’re going to drill, baby, drill.”

The siren song of the oil and gas industry! Literally: Drill, baby, drill! And Musk, he of the—I’m going to say it again—electric cars and “saving the world” schtick, didn’t pipe up until a full two minutes later, when he suggested that Trump set up a “government efficiency commission” to curb government spending. Later, he and Trump did have a brief exchange on the science of climate change. But Musk took pains to emphasize that the oil and gas industry isn’t the problem. “I’m pro-environment, but … I don’t think we should vilify the oil and gas industry, because they’re keeping civilization going right now,” he said.

This felt like a departure. Musk has spent a large chunk of his career casting himself as an environmental champion, sometimes going so far as to paint himself as the one man standing between the world and disaster. He has told the story of Tesla, in particular, as a hero’s journey to save the world through a transition to a sustainable energy economy. “I think I am objectively one of the world’s leading environmentalists in terms of doing things,” he said at an Italian political event last December.

In 2017, Musk told Rolling Stone about the clear existential threat of climate change with a flair that still feels familiar. “Climate change is the biggest threat that humanity faces this century, except for AI,” he said. “I keep telling people this. I hate to be Cassandra here, but it’s all fun and games until somebody loses a fucking eye. This view [of climate change] is shared by almost everyone who’s not crazy in the scientific community.” Musk has also regularly accused critics of carrying water for “fossil fuel companies.”

Oh, and remember that time (June 2017) that Musk quit three of Trump’s presidential councils after the US pulled out of the Paris climate accords? “Climate change is real,” he tweeted at the time. “Leaving Paris is not good for America or the world.”

Musk’s newer and wishy-washy approach to climate also reflects not only his very vocal embrace of far-right politics but also a new story he’s telling about Tesla. For the past few years, and especially as the chatter around artificial intelligence has hit a fever pitch, Musk has positioned his electric-auto maker as a path-breaker in robotic intelligence, too. In 2019, Musk announced that Tesla would have 1 million robotaxis on the road by the end of the year. (It didn’t). More recently, Tesla reportedly shifted resources from building a more affordable electric car, the mythical Model 2, to releasing a purpose-built robotaxi, even though the company has yet to reveal any true self-driving technology. (An unveiling event is scheduled for October.) Musk has said repeatedly that Tesla is an AI and robotics company and should be valued by investors as such. If Musk is backing off his endorsement of climate change science, it’s reasonable to ask if that relates to his marketing pivot for the most valuable car company in the world.

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August 16, 2024
The surprising wall pattern that could keep buildings cooler

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A building’s design can influence its temperature

Alistair Scott/Getty Images

Walls with a protruding zigzag pattern could stay up to 3°C (5.4°F) cooler than regular walls, without using any energy. This approach could reduce the energy used by cooling systems and thus help limit global warming.

“With this kind of design, we can have a cooler building,” says Qilong Cheng at Columbia University in New York. “So we can cut down energy consumption for cooling.”

The use of air conditioning is surging as the world heats up and the number of people who can afford it increases. Greenhouse gas emissions from cooling could more than triple by 2050. As a result, many teams are trying to develop passive cooling solutions that don’t require any energy.

For instance, simply making roofs white so they reflect more sunlight can keep buildings and cities cooler.

This approach is even more effective if roofs are coated with materials that reflect most sunlight but emit infrared radiation within the atmospheric transparency window. This is the range of wavelengths that isn’t absorbed by molecules in the atmosphere such as carbon dioxide.

“Infrared radiation within this band can pass through the atmosphere and reach outer space,” says Cheng.

While materials with these properties have a significant cooling effect on roofs facing upwards, they aren’t as effective on walls. The issue is that materials that are good at emitting infrared are also good at absorbing it, and surfaces near walls, such as concrete pavements, can radiate lots of infrared.

Cheng and his team’s solution is to have walls with a series of protrusions running parallel to the ground with a zigzag shape when viewed from the side. To visualise this, imagine a flight of stairs tilted up from a 45 to a 90 degree angle.

Crucially, the upwards-facing zigs – the treads in the staircase analogy – have a surface that emits lots of heat in the atmospheric transparency window, while the downwards-and-outwards facing zags – the risers – have a surface that reflects infrared heat rather than absorbing it.

To test the idea, the team built a 1-metre-high model with both zigzag and flat surfaces. When put outside in New Jersey during the summer, the zigzag surface was 2°C cooler, on average, over 24 hours than the flat surface, and 3°C cooler between 1pm and 2pm.

There are a number of cheap materials available with the necessary properties, says Cheng. Existing buildings could be retrofitted by adding corrugated panels. The interior cooling effect will vary depending on other factors, such as the size of the building’s windows, but simulations suggest it could be up to 2°C, reducing the energy needed for cooling by up to a quarter.

The zigzag cooling walls would only be suitable for hotter climes as they would increase the need for heating in winter in colder regions. But Cheng and his colleagues have also proposed a design with hinged “fins” that can be raised in winter to increase heat absorption and lowered in summer to minimise this.

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August 9, 2024
Each of the Past 12 Months Broke Temperature Records

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June 2023 did not seem like an exceptional month at the time. It was the warmest June in the instrumental temperature record, but monthly records haven’t exactly been unusual in a period where the top 10 warmest years on record all occurred in the past 15 years. And monthly records have often occurred in years that are otherwise unexceptional; at the time, the warmest July on record had occurred in 2019, a year that doesn’t stand out much from the rest of the past decade.

But July 2023 set another monthly record, easily eclipsing 2019’s high temperatures. Then August set yet another monthly record. And so has every single month since—a string of records that propelled 2023 to being the warmest year since tracking started.

On Wednesday, the European Union’s Earth-monitoring service, Copernicus, announced that it has now been a full year where every month has been the warmest version of that month since there’s been enough instruments in place to track global temperatures.

The history of monthly temperatures shows just how extreme the temperatures have been over the past year.Courtesy of C3S/ECMWF

As you can see from this graph, most years feature a mix of temperatures—some higher than average, some lower. Exceptionally high months tend to cluster, but those clusters also tend to be shorter than a full year.

In the Copernicus data, a similar yearlong streak of records happened once before, in 2015/2016. NASA, which uses slightly different data and methods, doesn’t show a similar streak in that earlier period. NASA hasn’t released its results for May’s temperatures yet—they’re expected in the next few days—but it’s very likely that the results will also show a yearlong streak of records.

Beyond records, the EU is highlighting the fact that the one-year period ending in May was 1.63 degrees Celsius above the average temperatures of the 1850–1900 period, which is used as a baseline for preindustrial temperatures. That’s notable because many countries have ostensibly pledged to try to keep temperatures from exceeding 1.5 degrees Celsius above preindustrial conditions by the end of the century. While it’s likely that temperatures will drop below the target again at some point within the next few years, the new records suggest that we have a very limited amount of time before temperatures persistently exceed it.

For the first time on record, temperatures have held steadily in excess of 1.5 degrees Celsius above the preindustrial average.Courtesy of C3S/ECMWF

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June 7, 2024
What is a heat dome and are they getting worse with climate change?

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High temperatures hit Joshua Tree, California, on 5 June 2024

Gina Ferazzi/Los Angeles Times via Getty Images

Mexico has been experiencing a severe heatwave due to a massive heat dome that has been affecting the country for weeks. Now this system has extended northwards into the southern US, causing extreme temperatures across a large region.

What is a heat dome?

A heat dome is not a clearly defined scientific term, but it is used by many weather forecasters. The American Meteorological Society defines it as an “exceptionally hot air mass that develops when high pressure aloft prevents warm air below from rising”. High pressure results in clear skies because sinking air warms as it descends – clouds form under the opposite circumnstances, with water droplets condensing out as rising air cools.

These high-pressure conditions mean lots of sunshine, which results in further warming and can dry out the soil, leading to less evaporation and a reduced chance of clouds and rain. These positive feedbacks can produce hotter and hotter conditions the longer the heat dome stays in one place. While heat domes cause heatwaves, there can be heatwaves without heat domes.

What makes high-pressure systems get stuck?

The jet streams are fast-flowing bands of wind in the upper atmosphere that usually help move weather systems along the planet’s surface. But sometimes big loops form in a jet stream, resulting in weather systems getting stuck in the loops. These blocking patterns, as they are known, can lead to extreme cold, extreme rain or, in the case of heat domes, extreme heat.

During the 2021 heat dome, several North American cities broke temperature records

Joshua Stevens/NASA Earth Observatory

How long do heat domes last?

They can last anywhere from days to weeks. For instance, an extreme heat dome over Canada and the northwest US in 2021 lasted nearly a month. During this event, the temperature reached nearly 50°C (122°F) in British Columbia, the highest ever recorded in Canada.

Are heat domes becoming more common as a result of global warming?

Heatwaves in general are becoming more frequent because of climate change, but most studies don’t look specifically at heatwaves caused by heat domes. There is a lot of debate about how warming will affect the blocking patterns that trap heat domes in place. A 2023 study concluded there will be an increase in “summer heat-dome-like stationary waves” over northwestern North America.

Are heat domes becoming hotter as a result of global warming?

Yes, this is certain. Because the world is now nearly 1.5°C warmer than in preindustrial times, when heat domes form today surface temperatures can get hotter than they previously would have. For instance, one study concluded the extreme temperatures recorded during the 2021 heat dome in Canada were “virtually impossible without human-caused climate change”. There is also some evidence that the intensity of heat domes is outpacing the warming trend, suggesting climate change is amplifying their intensity. “The intensities of hot extremes associated with… heat dome-like atmospheric circulations increase faster than background global warming in both historical change and future projection”, states a 2023 study.

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June 7, 2024
These photos show how a warmer climate is damaging Earth’s waters

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In her new book, Entropy, photographer Diane Tuft explores the damage that a warmer climate will have on bodies of water.

The Great Salt Lake in Utah (pictured above) is a stark example. Here, climate change has ramped up temperatures, while demands for fresh water from industry and agriculture have reduced the flowing of mountain streams to a trickle, shrinking the lake to two-thirds the volume of what it was in 2000. The colour split, captured by Tuft from a helicopter, is a result of differently pigmented algae that either live in high salinity (pink) or lower salinity (blue) water, bisected by a railroad causeway.

The second image, shown above, shows what was once a rice field in Kutubdia Island, Bangladesh, transformed into a field of salt. This is a country at peril from changing waters – projections suggest 17 per cent of it may be submerged by sea by 2050, with the saltwater making much of the land unsuitable for crops.

With one having too little water and the other too much, “both locations perfectly illustrate problems at the opposite ends of the spectrum”, says Tuft.

Photographer Diane Tuft
Publisher Monacelli/Phaidon

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April 24, 2024