One Saturday morning in November, Farhana Yamin took her place in a line of people gathered on Westminster Bridge and — when a signal was given — stepped off the pavement and into the road. As the crowd swelled, cars, black cabs and double-decker buses began to back up in nearby streets.

Similar scenes were unfolding on four other bridges over the Thames in a two-and-a-half-mile arc spanning the capital’s best-loved landmarks: Big Ben, the London Eye and St Paul’s Cathedral. In a festival atmosphere, protesters danced and passed around cupcakes. Among the thousands of first-time activists: families with kids; a banker; a teacher; a civil servant; grandparents; a vicar. Banners bore the name of the new movement: Extinction Rebellion.

Starting at 11am this Monday, the group plans to gridlock central London. Volunteers are due to peacefully occupy Parliament Square, Oxford Circus, Marble Arch and Waterloo Bridge. Participants have been asked to bring food and tents. Offshoots in cities across Europe and the US will stage parallel protests. After two previous attempts to get herself arrested, Yamin, an international environmental lawyer and one of the movement’s leading voices, hopes she will soon see the inside of a police cell.

“Every now and again I think, ‘What have I done?’” says Yamin, who helped midwife the 2015 Paris Agreement to curb greenhouse gas emissions, before growing disillusioned with the results of the 27 years she spent building coalitions to drive formal climate diplomacy. “I just got fed up with the environmental movement selling so much false hope when we’re still trashing the planet.”

Farhana Yamin, an international environmental lawyer and a leading figure in Extinction Rebellion: 'I just got fed up with the environmental movement selling so much false hope when we're still trashing the planet' © Charlie Bibby/FT

For decades, scientists have warned that burning too much coal, oil and gas will trigger runaway climate change. Last year, as megafires raged in California and the northern hemisphere languished in a record-breaking heatwave, global carbon emissions did not fall or even stay steady — they climbed to an all-time high.

If the curve does not start to bend soon, scientists fear that accelerating feedback loops could interact in catastrophic ways: collapsing ice sheets; faster-than-expected sea level rise; forest dieback; ocean acidification and thawing permafrost. Some have warned of the risk of a sudden shift to a new “hothouse” version of the earth. In this alien home, it is unclear how organised human life would survive.

Even as climatologists reveal the reality of the crisis in ever more granular detail, the environmental movement has tended to shy away from confronting people with graphic depictions of the dystopian future of harvest failure, starvation and anarchy that abrupt breakdown implies. Too much gloom, the thinking goes, only switches people off.

But the viral success of Extinction Rebellion since its launch in October last year suggests that attitudes might be changing. The word “extinction” in the movement’s title isn’t just referring to plants, insects and animals. It means us.

Gail Bradbrook is one of Extinction Rebellion’s founders and the closest person to a leader in a movement conceived as a self-organising, non-hierarchical “holacracy”. After growing up in a Yorkshire coal-mining family, Bradbrook went on to earn a PhD in molecular biophysics, and has been involved in environmental and social justice activism since her teens.

Gail Bradbrook, a leader of the group: with a PhD in molecular biophysics, she is adept at explaining the science of climate change and persuading people who have never previously broken the law that getting arrested can be fun © Charlie Bibby/FT

Juggling her responsibilities as a mother of two sons aged 10 and 13, she had been trying since the 2008 financial crash to catalyse high-impact social justice campaigns, but could never quite take them to scale. A few years ago, Bradbrook began to realise she had to tackle some sort of internal block.

If your government isn’t protecting you and the future of your kids, you have a duty to rebel and a right to rebel

A reluctant flier, she nevertheless travelled to Costa Rica to take a high dose of iboga — a psychedelic compound derived from a west African tree bark renowned for inducing visions. As the ceremony began, she offered up a prayer to be shown the “codes” for social change.

Transformed by the experience, Bradbrook ended her marriage, and began to work with a core group of activists including Roger Hallam, a Gandalf-like organic farmer who is studying a PhD at King’s College London in radical campaign design. A plan emerged: mass civil disobedience for bold climate action.

“The precedent is that civilisations collapse, and everything’s stacked up for this one to go, and it’s a mess when it happens,” Bradbrook tells me over coffee in between planning sessions. “So you might be good at banking, but you’re probably no good with a gun. The question for all of us is: ‘Where are we best placed to serve at the minute?’”

Inspired by the suffragettes, Mahatma Gandhi and Martin Luther King, Bradbrook and her team aim to create enough disruption to force the UK to declare a climate emergency, commit to a carbon-neutral economy by 2025 and establish “citizens’ assemblies” — chosen by lot like a jury — to democratically oversee such a monumental transition.

One of their slogans — “Tell the truth, and act like it’s real” — is resonating. Last month, hundreds of volunteers gathered in a converted warehouse on a Bristol canal for a weekend “spring uprising” festival — half party, half dress rehearsal for the planned London shutdown. Ranging in age from teenagers to retirees, groups took turns to role-play protesters locking arms and police trying to haul them away. A woman wearing a hi-vis vest supervised as the opposing teams grappled and yelled.

When the exercise was over, Bradbrook strode on to a stage to address the packed hall, giant banners saying “Rebel for life” slung from a gallery. Combining her academic bona fides with a plain-English rendition of the latest climate science, Bradbrook has developed a knack for persuading people who have never previously considered breaking the law that being arrested can be fun.

As she spoke, a photograph flashed up on a screen showing Bradbrook chatting amiably with a female officer leading her away from a protest outside the Department for Business, Energy and Industrial Strategy, where she and other Extinction Rebellion volunteers had sprayed washable chalk graffiti to demand the government ban fracking. It had turned out that the officer was a vegan. Bradbrook joked that the only thing she didn’t like about getting arrested was the paperwork.

“If your government isn’t protecting you and the future of your kids, you have a duty to rebel, and a right to rebel,” Bradbrook told the audience. “When you say ‘no’ and you get on the streets and you do an act of civil disobedience, it changes your psychology. Some of us need to turn the herd.”

Last July, as train tracks in Britain buckled in the heat and sales of paddling pools soared, Jem Bendell, professor of sustainability leadership at the University of Cumbria, published a paper entitled “Deep Adaptation: A Map for Navigating Climate Tragedy”. In contrast to most scientific papers, read by only a handful of academics, “Deep Adaptation” has been downloaded more than 350,000 times. The paper also earned in-depth coverage from the digital magazine Vice, which ran its story under the headline: “The climate change paper so depressing, it’s sending people to therapy.”

Over 36 meticulously referenced pages, Bendell set out the thinking behind his conclusion that non-linear climate impacts mean that the collapse of industrial society is now inevitable, probably due to massive harvest failures, perhaps within a decade or so.

“When we contemplate this possibility, it may seem abstract . . . But when I say starvation, destruction, migration, disease and war, I mean in your own life,” Bendell wrote. “With the power down, soon you wouldn’t have water coming out of your tap. You will depend on your neighbours for food and some warmth. You will become malnourished. You won’t know whether to stay or go. You will fear being violently killed before starving to death.”

Last month’s Extinction Rebellion ‘spring uprising’ rally in Bristol: 'half-party, half dress rehearsal for the planned London shut-down' © Charlie Bibby/FT

If the paper seemed bleak, Bendell argued that an impulse among many of his colleagues to try to “balance out” the raw implications of climate science with positive but ultimately futile examples of progress in the sustainability field was a bit like discussing the health and safety policies of the White Star Line with the captain of the Titanic.

Rather than accept demands for substantial revisions made by the editors when he submitted the paper to a policy journal, he published “Deep Adaptation” as an occasional paper through his university. “As we are considering here a situation where the publishers of this journal would no longer exist, the electricity to read its outputs won’t exist, I think it time we break some of the conventions of this format,” Bendell wrote.

Though Bendell wrote his paper with touches of dark humour, he told me that he intended it as an invitation for “post-denial” students and colleagues to begin a pragmatic discussion on how best to support individuals and communities to prepare for collapse not just in a practical sense, but also by exploring the psychological and spiritual implications.

Far from retreating into depression or apathy, Bendell noted that his mature students, when discussing his findings in a supportive environment, tended to experience “a shedding of concern for conforming to the status quo” and a new creativity about what to do next.

Among Bendell’s readers was Andrew Medhurst, a 30-year veteran of the City who had taken a job in a government-backed workplace pension provider at the start of 2018. He had been reading up on climate change, found Britain’s blistering summer unnerving and downloaded “Deep Adaptation”. At 53, Medhurst could look back on a varied career in finance, postings in south-east Asia and the rewards of raising his two children, Lottie, 18, studying at drama school, and Henry, 23, a visual effects artist. He began to wonder how much time they might all have left.

Andrew Medhurst left his job in finance to devote himself to the movement: 'Lots of people understand climate change is real but they don't see the emergency' © Charlie Bibby/FT

A few weeks later, Medhurst’s foreboding deepened when the Intergovernmental Panel on Climate Change, a UN-sponsored panel of scientists, reported that the world would have to slash carbon emissions by about 45 per cent by 2030 to keep warming close to the 1.5C target agreed in Paris. The risks of letting temperatures rise by 2C — previously considered a fairly safe limit — were laid out: the loss of 99 per cent of the world’s coral reefs; a thaw in permafrost equivalent to the area of Mexico; hundreds of millions of people plunged into poverty; and a heightened risk of the climate system hitting tipping points.

Medhurst, a former senior compliance and risk manager in Lloyds’ corporate banking division, did not see halving emissions as likely. In November, he joined the Extinction Rebellion bridge-blocking protest at Waterloo, accompanied by his wife Kate, who had spent much of her career at Bank of America Merrill Lynch, and their dog, a Löwchen named Mia.

We’re encouraging our children to invest in a financial product they may need when they are 50. What they may need is food and shelter — not a share portfolio

As Medhurst learnt more about how some climate impacts were materialising much faster than scientists had anticipated, he concluded that he could no longer continue selling pensions with a clear conscience.

“We’re not only destroying the planet for our children and grandchildren, but we’re actively encouraging them to invest into a long-term financial product that they may need when they are 50,” says Medhurst, a tall, self-possessed man whose voice can nevertheless start to crack when he contemplates the grimmer scenarios. “What they may need is food and shelter — not a share portfolio.”

In February, Medhurst resigned from his job to devote himself to Extinction Rebellion, where he helps manage the budget — provided by a mix of philanthropic foundations, individuals, crowdfunding and corporate donations. Every few weeks he gives versions of the “talk” — a mix of climate science and social change theory — designed to recruit more volunteers for the civil disobedience campaign.

On a recent Thursday evening, Medhurst drove from his smart home in south-west London to address about 30 well-heeled listeners at the Quadrangle, a restored Victorian model farm in Shoreham, Kent, where he had once played cricket as a graduate at Midland Bank.

“Lots of people have heard about climate change, lots of people understand it’s real — but they don’t see the emergency,” Medhurst said during the drive. “They think what I thought a couple of years ago: that sea levels are going to rise by a couple of millimetres by the end of the century. No — this is really, really scary.”

By the end of the talk, about half the audience had filled out contact forms. Two of them had ticked a box saying they would be willing to be arrested.

Cory Doctorow, a science fiction writer and activist, uses the term “peak indifference” to refer to the way societies seem incapable of acting in the face of overwhelming problems until they become impossible to ignore. From the Amazon rainforest to remote parts of Africa, community leaders have long been fighting — and often dying— to defend their ecosystems from an onslaught of agribusiness, mining and oil companies.

Volunteers in the north London office serving as Extinction Rebellion’s headquarters aren’t running the same risks. Nevertheless, the scenes of young people poring over laptops and complex wall charts could be read as evidence that “peak indifference” may finally have passed in the rich world too.

Since the summer, demands for climate action have exploded. In the US, Alexandria Ocasio-Cortez, the Democratic congresswoman, and her supporters in the youth-led Sunrise Movement have provided a rallying point with a proposed Green New Deal, which ties a low-carbon future to concerns over jobs, wages and economic justice.

A lone protest by Greta Thunberg, a 16-year-old Swedish climate activist, inspired a global school strike that mobilised an estimated 1.5 million children and students on a single day last month — including Medhurst’s daughter Lottie, who skipped rehearsals to join a march to the gates of Buckingham Palace. Thunberg’s clear-eyed message to business leaders in Davos: “I don’t want you to be hopeful, I want you to panic. I want you to feel the fear I feel every day — and then I want you to act.”

Bill McKibben, a US climate writer and activist, who was arrested at the White House in 2011 while protesting against a new pipeline, says it would be a mistake to judge such movements solely on whether their immediate demands are met.

“The prize that activists are playing for is to change the zeitgeist, to change people’s idea of what’s natural and normal and obvious,” says McKibben, who co-founded 350.org, a campaign that has persuaded investors to divest billions of dollars from fossil fuel companies. “And if we can change the zeitgeist, then legislation and so on will follow fairly easily.”

Extinction Rebellion volunteers roleplay protesters locking arms and police trying to haul them away © Charlie Bibby/FT

Nevertheless, civil disobedience is a delicate art — especially in the toxic political climate unleashed by Brexit. The violence that erupted in France during anti-establishment gilets jaunes protests has left some in Britain especially wary of any signs of a slide into “ecofascist”-style mob rule.

Mark Stevenson, a futurist and author, says he feels inspired by Extinction Rebellion’s ambition, but warns that disruptive protest could easily backfire. “My fear for them is that if they get it wrong they could end up making an enemy of the very people they need to bring along,” he says.

Though Extinction Rebellion volunteers do their best to explain their cause to blocked motorists, sometimes with offers of cake, not everyone is sympathetic. At a recent London protest, where traffic was slowed to a crawl, a man in the cab of a white van yelled in frustration: “They should get a job!” Nigel Farage, the Brexit campaigner and LBC radio host, has called the campaign “economic terrorism”.

Corinne Le Quéré, professor of climate change science at the University of East Anglia, who undertook groundbreaking work on a global carbon budget, says the wave of concern over climate change would be better channelled into an aggressive but methodical long-term response. “Many people say ‘Oh, we need a tipping point, and everything will go pretty quickly,’” she says. “Maybe — but I think a social tipping point is pretty unstable.”

The British state’s tolerance for dissent has hard edges. In March 2017, 15 protesters cut the fence at Stansted Airport, north of London, and chained themselves to the wheels, nose and wing of an airliner to stop asylum seekers being deported. Although they escaped jail, the “Stansted 15” were convicted under laws drawn up to prosecute terrorists. They could have been sentenced to life.

Alison Green, a cognitive psychologist and former pro-vice chancellor of Arden University, prides herself on being the hyper-rational opposite of a “touchy-feely” social scientist. But she is the first to admit that her years of research into human problem-solving left her ill-equipped to understand her own experience of climate grief.

It began with the heatwave. Green noticed that the leaves of the plane trees on the Cambridge commons were parched and brown. The tarmac outside her house started to melt and the earth at her allotment was baked so hard she couldn’t get a fork in to turn it. The water pumps ran dry. Seeds she planted refused to germinate, and seedlings she coaxed out of soil in cardboard boxes on her dining table died within a few days of planting out. The fields seemed empty of crops. “It was scary,” Green says. “And no one was talking about it.”

Alison Green, a cognitive psychologist, resigned from her job to support Extinction Rebellion. Last year's heatwave 'was scary. And no one was talking about it' © Charlie Bibby/FT

Green began to read about climate change. “For a month, I went around in shock. I just saw the world completely differently,” she says. “I suddenly felt so incredibly vulnerable — I realised just how fragile life on the planet really is.”

Concerned that her colleagues were unaware of the gravity of the situation, Green started handing out climate science papers at work. Nobody denied there was a problem, but people tended to grow uncomfortable if the discussion went on too long and meetings would quickly move to the next agenda item: budgets, staffing, curricula.

“I had this really rude awakening where I realised that my career was completely pointless — it was irrelevant, it was meaningless,” Green says. “Either I’m going to continue doing what I do and not sleeping well at night because of the crisis that we’re in, or I’m going to jump ship. How can we knowingly educate students for a future that doesn’t exist?”

A friend of hers coined a phrase — “ecophany” — to describe Green’s metamorphosis. She has since resigned from her job to support Extinction Rebellion, persuading hundreds of academics and scientists to endorse its principles. Green has also started volunteering as UK director of Scientists Warning, a public engagement group.

Her biggest frustration is with those who tell her privately that they support Extinction Rebellion’s aims but do not want to say so publicly for fear of harming their careers. “There’s still this view — and it does prevail in academia — that you work within the system,” Green says. “What they don’t yet get is that the system is the cause of the problem. Either we dismantle this edifice that we’ve built, or it’s going to crumble.”

The ecologist Joanna Macy describes the “colossal anguish” people feel at the devastation of the natural world as “a great public secret”. Extinction Rebellion commands such loyalty not because all of its volunteers necessarily believe they will succeed. More than a vehicle for protest, the movement offers a spiritual refuge from the grinding cognitive dissonance of living in a society where the gap between what science says needs to happen and what people are actually doing looms large.

“It is as though the world’s astronomers were telling us that an asteroid is heading our way and will make a direct hit destined to wipe out all of life, to which the public responds by remaining fascinated with sporting events, social media, the latest political scandals and celebrity gossip,” wrote Catherine Ingram, a retreat leader and author, in a February essay entitled “Facing Extinction”.

“No matter how clear and rational our understanding of the situation, many of my extinction-aware friends admit that the magnitude of the loss we are undergoing is unacceptable to the innermost psyche,” she added. “It might be akin to a parent losing a young child… Only this time, it is all the little children. All the animals. All the plants. All the ice.”

Zhiwa Woodbury, a public interest attorney and ecopsychologist affiliated with the California Institute of Integral Studies, believes the world’s paralysis in the face of climate change can best be explained through the lens of what he terms “climate trauma” — the overwhelming realisation that the earth’s life-support systems are starting to break down. The natural impulse to resort to denial or distraction as a coping mechanism won’t work for long because the human psyche isn’t ultimately separate from nature.

Thus the knowledge of an ever-present, ever-growing threat to the biosphere is serving as a kind of universal catalyst to bring the unresolved trauma buried in every individual, culture and society to the surface. On this reading, the challenge to the liberal order posed by Brexit and Trump could be symptoms of a more profound unravelling.

The global school strike on March 15 © Charlie Bibby/FT

“There’s something fundamental about us that’s intimately connected to the natural world. If that relationship breaks down — which it has — then every relationship will go,” Woodbury tells me. “That’s actually hopeful, because it basically says that if we focus on the way we relate to each other, to ourselves and to the world, we can come out of this.”

Extinction Rebellion is one of a number of new groups to emerge, such as the Dark Mountain Project in the UK, where talking about how terrified, angry or numbed you feel about the climate crisis is not only acceptable but welcomed. Just as some terminal patients begin to perceive each moment of life as a miracle after receiving their diagnosis, a deep reckoning with the implications of climate change can sometimes trigger a similar awakening.

A poster at Extinction Rebellion’s London office says: “Give yourself time to feel — grief opens pathways of love, and melts the parts of you that are frozen.” Twice a week, facilitators hold an online video conference for anyone who wants to explore their climate trauma called “The Skill of Brokenheartedness”.

Extinction Rebellion’s unflinching relationship with grief is visible in the movement’s fondness for macabre imagery — mock coffins, buckets of fake blood and paper skulls — but the mischief-makers who dream up its actions also know the power of humour. On April Fool’s Day, 13 volunteers were arrested for stripping almost naked in the public gallery of the House of Commons to draw attention to the climate crisis during a Brexit debate. A photo of the defiant display snapped by an MP made headlines around the world.

Representatives of theatres, art galleries and museums aligned with Extinction Rebellion stage a horse-led procession to declare a climate emergency, London, April 3

Gail Bradbrook says there is no better place to confront the heartbreak of climate change than a custody suite. In her experience, being arrested has a “spell-breaking” quality, transmuting society’s deeply ingrained pressures to conform into a new-found sense of personal power.

Several other Extinction Rebellion volunteers have reported similar epiphanies: one underwent an emotional catharsis as — alone in her cell — she finally felt safe to weep her deepest tears; another sensed a powerful connection with a lineage of freedom fighters past.

The roll-call grows. Extinction Rebellion says more than 200 volunteers have been arrested since October. They include four who disrupted a council meeting in Norfolk over plans to build a new road; nine who glued themselves to glass at a Mayfair hotel hosting an oil conference; and another nine who staged a “die-in” at the Rockefeller Center skating rink in New York.

Last month, Stephen McDonald, 62, a builder-decorator, and another man were convicted of criminal damage for attempting to dig a mock grave during a funeral-themed protest in Parliament Square. McDonald, who has three grandchildren, had never been in trouble with the law before.

Bradbrook says people used to look at the floor when she called for arrestees at the end of the “talk”. “I may as well have said, ‘Can you just get undressed and crap in the corner?’” she says. Now, more and more say: “Bring it on.”

Yamin, the international lawyer, who is also a trustee of Greenpeace UK and will soon take up an advisory role at the World Wildlife Fund, wants to build a bridge with existing organisations to forge a much bigger “movement of movements”. “We need to tap into the new form of leadership that’s being asked of us now,” she says. “Why would I want to be earning a nice salary when so many others are dying to defend Mother Earth?”

Will all these sacrificial acts achieve anything? Climate models and social systems share a propensity to sudden, hard-to-predict shifts that can lead to a new status quo. In earth sciences, that’s usually bad news. But contemplating non-linear change can also be a source of inspiration. Extinction Rebellion and its allies believe there may still be time to catalyse an evolutionary leap towards a saner model of planetary stewardship.

Clad in a crimson coat and matching hat as she dashes between fundraising discussions with a London hedge-fund owner and meetings to rally Extinction Rebellion volunteers, Bradbrook tells me she now knows that she would — if necessary — give her life for the cause. “It’s to reimagine society in a way that makes sense to us all,” she says. “I know that sounds like a hippy dream. But the point is, if we don’t do it — we are f***ed.” Her phone bears a sticker of Extinction Rebellion’s insignia: a stylised design of an hourglass.

Matthew Green reported for the FT from Pakistan and Afghanistan and is the author of “Aftershock: Fighting War, Surviving Trauma and Finding Peace”

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Letters in response to this article:

Protesters should be left to stick to their principles / From David Taylor, Bristol, UK

Protesters can’t be bothered with democracy / From Helen Jackson, Saffron Walden, Essex, UK