The scene could be straight from a science-fiction film: a vision of everyday life, but with one jarring difference that makes you realise you’re on another planet, or in a distant future era.

A sports class is in full swing on the outskirts of Beijing. Herds of children charge after a football on an artificial pitch, criss-crossed with colourful markings and illuminated in high definition by the glare of bright white floodlights. It all seems normal enough – except for the fact that this familiar playground scene is taking place beneath a gigantic inflatable dome.

“It’s a bit of a change having to go through an airlock on the way to class,” says Travis Washko, director of sports at the British School of Beijing. “But the kids love it, and parents can now rest assured their children are playing in a safe environment.”

The reason for the dome becomes apparent when you step outside. A grey blanket hangs in the sky, swamping the surroundings in a de-saturated haze and almost obscuring the buildings across the street. A red flag hangs above the school’s main entrance to warn it’s a no-go day: stay indoors at all costs. The airpocalypse has arrived.

Beijing’s air quality has long been a cause of concern, but the effects of its extreme levels of pollution on daily life can now be seen in physical changes to the architecture of the city. Buildings and spaces are being reconfigured and daily routines modified to allow normal life to go on beneath the toxic shroud.

Paper face masks have been common here for a long time, but now the heavy-duty kind with purifying canister filters – of the sort you might wear for a day of asbestos removal – are frequently seen on the streets. On bad days, bike lanes are completely deserted, as people stay at home or retreat to the conditioned environments of hermetically-sealed malls. It’s as if the 21-million-strong population of the Chinese capital is engaged in a mass city-wide rehearsal for life on an inhospitable planet. Only it’s not a rehearsal: the poisonous atmosphere is already here.

The British School is the latest of Beijing’s international colleges to go to the drastic lengths of building an artificial bubble in which to simulate a normal environment beneath the cloak of smog. Earlier this year, the nearby International School of Beijing lavished £3m on a pair of domes covering an area of six tennis courts, with hospital-grade air-filtration systems, following the lead of the Beijing satellite of exclusive British private school Dulwich College, which opened its own clean-air dome last year.

“Pollution is what all the parents are talking about,” says Nicole Washko, Travis’s wife, who also works at the school where their two daughters go, too. “More and more ex-pat families are leaving this country for the sake of their kids’ health. So if all the other schools have a dome, then we’ve got to have a dome.” A non-toxic learning environment is perhaps the least parents might expect, when they’re paying £20,000-a-year fees.

The British School has recently undergone a complete filtration overhaul, as if preparing for atmospheric armageddon, with new air curtains installed above the doors and almost 200 ceiling-mounted air purifiers put in to complement the floor-standing kind in each classroom. Windows must remain closed, and pupils must adhere to the strict air safety code. Reception classes stay indoors when the air quality index (AQI) hits 180 – measured on an official scale of 500 by various sensors across the city. For primary kids the limit is 200, while the eldest students are allowed to brave the elements up to 250. Anything above 300 and school trips are called off. The World Health Organisation, meanwhile, recommends a safe exposure level of 25.

“We were finding our sports fixtures were being cancelled so often, and kids were getting cabin fever from being kept in doors so much of the time,” says Travis Washko. “But now we have the dome, it’s perfect weather all year round.”

The day I arrive in Beijing, the AQI hits 460, just 40 points away from maximum doom. It’s the kind of air that seems to have a thickness to it, like the dense fug in an airport smokers’ cubicle. It sticks in the back of your throat, and if you blow your nose at the end of the day, it comes out black. Peddling around the city (I am one of the only cyclists mad enough to be on the road) is an eerie experience – not just for the desolation, but for the strange neon glow coming from signs at the top of invisible buildings, like a supernatural, carcinogenic version of the northern lights. The midday sun hangs in the sky looking more like the moon, its glare filtered out by the haze.

Daily talk of the AQI has become a national pastime amongst ex-pats and Chinese locals alike. Air-quality apps are the staple of every smartphone. Chinese microblogs and parenting forums are monopolised by discussions about the best air filters (sales of the top brands have tripled over the last year alone) and chatter about holidays to “clean-air destinations” like Fujian, Hainan and Tibet.

This year’s Beijing marathon, held on a day that exceeded 400 on the scale, saw many drop out when their face-mask filters turned a shade of grey after just a few kilometres. Some said it felt like running through bonfire smoke. With such hazardous conditions increasingly common, it’s not surprising that foreign companies are now expected to pay a “hardship bonus” of up to 20 or 30% to those willing to work in the Chinese capital.

And yet denial still persists. Many Beijingers tend to use the word “wumai” (meaning fog), rather than “wuran” (pollution), to describe the poor air quality – and not just because it’s the official Newspeak of weather reports. It’s partly because, one local tells me, “if we had to face up to how much we’re destroying the environment and our bodies every day, it would just be too much.” A recent report by researchers in Shanghai described Beijing’s atmosphere as almost “uninhabitable for human beings” – not really something you want to be reminded of every day.

When I first came to Beijing in 2003, as a volunteer English teacher, my students told me that the city’s air wasn’t nearly as bad as London’s. “We know about your ‘pea-soupers’,” they would say, conjuring images of ye olde England shrouded in Dickensian gloom, happily ignoring the murky haze outside their own classroom window (then more often caused by sand storms than coal-burning power plants). Ten years later, the same former students are all too aware of the problem.

“We never used to have days as bad as this,” says Li Yutong, who has recently returned to Beijing after several years studying in Australia and working in Hong Kong. “I used to play football outside and go running, but you just can’t do that any more. School kids seem to get sick more often now – and they’re much fatter because they don’t play outside.”

Our school was sited across the street from the national Centre for Disease Control and Prevention, which proved to be an alarming neighbour when SARS broke out and we watched the constant train of ambulances. Now its attentions have turned to an airborne threat of a different kind. In June, the centre released data which suggested that the average 18-year-old Beijinger will spend as much as 40% of their remaining years in ill-health – potentially suffering from cancer, cardiovascular or respiratory disease. Breaking the usual government silence on the issue, China’s former health minister, Chen Zhu, spoke out in January to reveal that between 350,000 and 500,000 people die prematurely each year here as a result of air pollution.

In response to mounting pressure, the government has introduced a host of new laws and regulations, increasing fines for environmental violations, and attempting to shut down high carbon-emission factories. But there is little to suggest any of their measures are having an effect.

“To be able to monitor these factories, local officials are supposed to visit them in person,” says Zhang Kai, lead campaigner on air pollution at Greenpeace East Asia. “But there is just no capacity to do that, and no policy in place to punish the polluting factories effectively.”

The national “airmageddon” has spawned a host of other attempts to solve the problem, ranging from the miraculous to the madcap. In the western city of Lanzhou, officially deemed by the World Health Organisation to have the worst air in China, officials have proposed digging great gullies into the surrounding mountains in the hope of trapping polluted air in a gigantic landscape gutter, like an atmospheric ha-ha. But Lanzhou’s poor air quality is caused less by burning coal and car fumes than by the local penchant for blowing up mountains with dynamite. More than 700 peaks are being levelled to provide swathes of flat land for development, and blowing out a huge gulley would only add to the problem.

Other solutions proposed in Beijing have a more futuristic air. Environmental scientist Yu Shaocai has proposed fitting water sprinklers to the tops of tall buildings, to try and “wash” the smog out of the sky. “Water should be sprayed into the atmosphere like watering a garden,” Yu wrote in the journal Environmental Chemistry Letters, noting that most urban pollution hangs below 100m, so it could be caught by an artificial shower from the city’s taller towers. An expert in “wet deposition” (how rain can clean particles from the air), he thinks he’s got the science sorted, and the main challenge is just to “design the specific spray system that can spray a good raindrop size and [ensure] the most scavenging efficiencies for the air pollution.” But his hastily Photoshopped visuals of garden sprinklers stuck on top of skyscrapers don’t do much to inspire confidence.

In fact, wet deposition has long been hailed as a possible solution by higher powers, with their lofty pretensions to control the elements. China’s Meteorological Administration issued a paper last year which ambitiously declared all local officials would be able to use artificial rain to clear away smog by 2015. And as the Washington Post reported, the idea might not be so far from reality: because of chronic water shortages, China has invested heavily in artificial rain since the late 1950s. The country now boats a battery of 7,000 cloud-seeding artillery guns, the same number of launchers for chemical-bearing rockets, and more than 50 planes – all manned by an army of 50,000 employees, ready to launch full-scale warfare on the weather.

At the other end of the scale are the initiatives that aim to affect people’s attitudes on the ground. Driven by an effort to raise awareness of the smog problem and spur the government into action, a host of critical art projects have been spawned. British artist Matt Hope has designed a “breathing bicycle”, a home-made Heath Robinson-style contraption that filters air as you pedal along and feeds it through a tube into a fighter-pilot breathing mask. Cycling around the hutong alleys, looking like Darth Vader being attacked by a hoover, he’s certainly attracted some funny looks.

“It’s a provocational prototype,” Hope says. “It’s pretty archaic, but then burning coal is pretty archaic too. It’s an intentionally ridiculous solution to a ridiculous problem.”

Another plucky Dutch designer thinks he can turn the pollution into a lucrative commodity. Over the past few months, Daan Rossegaarde has been meeting with the mayor of Beijing to talk through his plan for “electronic vacuum cleaners” to be installed in parks across the city, to suck smog from the skies. It might sound far-fetched, but he says his working prototype should be ready by next summer.

“I want to move away from statistics and the usual factsheet discussion,” says Roosegaarde, talking at excitable break-neck speed, a man on a mission. “If you create a place that’s 75% cleaner than the rest of the city, you create a powerful incentive for people to clean the whole city.”

His proposal, developed in partnership with scientists at the Technological University of Delft in the Netherlands, uses buried coils of copper to create an electrostatic field that attracts smog particles, creating a kind of halo of clean air above it. “It’s similar to how static electricity attracts your hair,” Roosegaarde says. “We charge the smog particles and suck them to the ground.”

He has also developed a mobile version which uses the same technology, but housed in a vertical totem-pole structure that sits atop a small temple-like pavilion, akin to those found in Beijing’s parks. It’s here where the real alchemy will happen. “We’re going to turn dust into diamonds,” Roosegaarde says. “We will condense a 1,000 cubic metres of smog down into a millimetre-cube carbon crystal – which we will set like a diamond on a ring.” When you buy a smog ring, he says, you’re effectively donating 1,000 cubic metres of clean air to the city.

“I like the idea that you can take a problem and turn it into something desirable,” Roosegaarde adds. “Of course it’s not a practical solution, but I’m hoping that smog jewellery will get people talking about the problem – and when they see these clear circles of blue sky above the parks, they’ll demand clean air for the whole city.”

The volume of discontent has been rising since Beijingers got a chance to see exactly what clear blue skies looked like last month, when miraculous weather was laid on for visiting world leaders, in town for the high-profile Apec summit. With the kind of draconian measures unseen since the 2008 Olympics, the entire region was locked down to guarantee clear skies for the precious week. Production in all factories within a 125-mile radius of the city was suspended, half the cars were banned from the roads, schools were closed, and public-sector workers were given compulsory holidays. No weddings were registered, no passports issued, no taxes paid, no fresh products delivered, and no banks open. Bodies went uncremated and burials were partly suspended.

The result? A climatic Potemkin facade of perfect blue skies – which soon became an internet meme, coining the term “Apec blue”.

“It’s not sky blue or ocean blue. It’s not Prussian blue or Tiffany blue,” wrote one user of the microblogging site, Weibo. “A few years ago it was Olympic blue, and now it’s Apec blue.” It quickly came to mean something of fleeting, artificial beauty, probably too good to be true. “He’s not really into you,” went one recurring online saying. “It’s just an Apec blue.”

Returning to Beijing during the Apec week was like arriving in a completely different city. What had been a ghostly world of streets that disappeared if more than a block away, became a wide-open place of grand avenues terminating at distant mountains, visible for the first time.

And back at the British School, the smog dome was empty. Pupils were enjoying a rare outdoor lesson beneath a different kind of artificial roof – the crystal clear canopy of Apec blue.