Nothing like a dame: How Vivienne Westwood traded a couture lifestyle for the front line of the eco war

Vivienne Westwood would rather we saved the planet than bought her dresses these days, and her campaign against global warming has taken her everywhere from the G20 protests to... a first-class seat on a Virgin Atlantic flight? Harriet Walker listens in as the maverick fashion designer persuades Richard Branson, the airline's owner, to join her mission

It's a war," says Vivienne Westwood, thumping out the syllables on her tartan-clad leg. "It's a war for the very existence of the human race. And that of the planet." The inimitable British fashion designer is on board a plane bound for New York to celebrate Virgin Atlantic's 25th anniversary, but it isn't a birthday greeting she has for Richard Branson. Rather, she is here to interview him about his green policies and find out how his company is reacting to what she sees as an imminent threat to our cosy, and often excessive, lifestyle. And she's ready for battle, in an army cap from her own collection and a badge emblazoned with the logo of her Active Resistance movement.

Active Resistance is a project Westwood set up in 2005 to encourage engagement with humanitarian and environmental issues. "I am traumatised by the problem of climate change," she says in her crisp but warm Derbyshire burr. "It first hit me when I read an article by [the science researcher] James Lovelock, in which he predicted that in 100 years there'd be only, if we're lucky, one billion people left. That was just such a shock." Since then, Westwood has become a vigorous champion of Lovelock, and cites his Gaia theory – named after the Greeks' earth goddess and positing that the planet is a self-regulating life-system, adapting to the pressures it finds itself under – as the most important extant work on climate change.

Westwood is known for speaking up for what she believes in; in fact, she made her name doing it when she and then-husband Malcolm McLaren opened their shop, called Sex, on the King's Road in the 1970s and created an aesthetic which gave identity to the punk movement. She received an OBE in 1992 and was made a Dame in 2006 but, far from being absorbed into the establishment, Westwood is still questioning it – this time not with safety pins and bondage trousers, but with an astute self-taught intellectualism and a righteous, heartfelt passion that infects her fans, her audiences and, in the case of Richard Branson, her interviewees.

"I suspect we've both discovered the horrors of climate change at the same time," he says, as they settle into a pair of Upper Class seats. "Obviously, as an airline owner, I have a fair amount of guilt, and a fair amount of responsibility to redress my carbon footprint." To assuage this guilt, he says, 100 per cent of the profits from his five airlines and his train company are being reinvested into trying to create a clean fuel. "We've developed something called isobutanol, which doesn't emit any carbon and which we hope will be powering our planes in maybe five or six years' time."

Westwood's activism is well known within the fashion industry. Her recent collections have had such names as Propaganda, Active Resistance, and Chaos, while her autumn/ winter collection, shown in Paris in February, was called +5o, a reference to the temperature Lovelock predicts the Earth will increase by when carbon dioxide exceeds certain levels in the atmosphere. The actor and pin-up Pamela Anderson modelled a logo T-shirt in the show and features in the ad campaign. Though as a designer Westwood finds inspiration in art and historical costume, her sensibilities are rooted in the present, even the future: "We're all in it together. And what is the future if we don't do anything anyway?" Last year she launched her manifesto, "Active Resistance to Propaganda", which takes the form of an imagined confluence of characters as diverse as Aristotle, Alice in Wonderland and Pinocchio, and focuses on the cultural and political inertia brought about by excessive consumption in modern life.

Consumerism is a tricky fight to pick when you're an internationally acclaimed and commercially successful designer – even more so when you're using it as a method of approaching the carbon problem while on a transatlantic flight – but Westwood is not cowed. "I might never go to New York again," she admits. "There's guilt in my heart and I'm part of the problem. I don't think I should expand into different countries – I've really got problems with that now."

It would be easy to accuse Westwood of hypocrisy, given the multinational nature of her clothing empire, but she is one of few in the fashion industry actually taking the environment, and her role in it, seriously. She is a restless activist, an idealist who wants to rally people to accomplish something she thinks we are all capable of. "The most important weapon we have is public opinion: go to art galleries, start to understand the world you live in. You're a freedom ' fighter as soon as you start doing that, and you get a perspective on everything, not just on consumer life."

So, are we all guerrillas in the war on climate change? "Calling it a war is what we need, otherwise there's no chance." Westwood herself attended London's G20 protests in April in a bandanna that read "Chaos".

Branson picks up the war theme in inviting Westwood to an event he is hosting later in the week: "We decided to set up a 'Carbon War Room'," he says. "Carbon is the enemy and billions of people are going to get killed. Churchill set up a war room, so we should too." Several specialists are involved in the venture, which aims to cover every aspect of environmental policy. "We'll try to go after the low-hanging fruit of each sector initially," he continues "and try to advise the Government, industry and the public."

"I like your phrase 'the low-hanging fruit'," replies Westwood. "It's like the lungs of the world – you can't do without them, and we need to breathe." She is breathless herself at the thought of future generations suffering, and at the prospect of Branson's climate summit, but refuses to sentimentalise the subject, and is rigorous in her interviewing technique: she knows the science and practicalities of corporate climate policy, and the arguments for and against many of the tactics from her extensive reading. She cites Six Degrees by Mark Lynas and Lovelock's The Vanishing Face of Gaia, the latest in his series of books, as essential reading, and interviewed the scientist for this month's issue of the British style magazine Dazed & Confused.

"Lovelock talks about us as 'tribal carnivores'," says Westwood. "We've been a success because we work together in packs and teams, but we're very much follow-my-leader and wait for people to tell us what to do. It's the sort of evolutionary programme we have, and it can be an asset, but it can also be a terrible thing."

Westwood and Branson are both trendsetters, pioneers in their own spheres. After punk, Westwood created some of the most recognisable and most imitated designs in the world – the pirate boot, the mini-crini – while Branson first opened his Virgin record stores in the 1970s, selling records at much lower prices than his competitors, before signing bands, developing the record label and forming Virgin Atlantic in 1984 and Virgin Mobile in 1999. He is also developing travel beyond the Earth's atmosphere with Virgin Galactic, the first flight of which Lovelock is famously booked on to. "He keeps calling me and saying, 'Hurry up, Richard,'" he relates cheerfully, pleased to give a glimpse of Gaia from above to a man whose work has given us a glimpse of a future we must try to avoid.

Both Westwood and Branson believe in the need for more information: that the Government and business owe it to the public – if not to Gaia herself, to use Lovelock's terms – to find practical solutions to the problem. "There has to be a sense of urgency," says Branson. "We put up a $25m prize for anybody who could come up with a way of extracting carbon from the Earth's atmosphere. Obviously rainforests extract carbon, but we need to come up with another method."

One such potential solution is "biochar", a charcoal created by decomposing biological matter, which is then stored in the ground, rather than released as carbon. Thus, waste products from farms, factories and homes are ploughed into fields, where they become fertiliser. "If every farmer did it, it would cancel out all the liquid fuels – so everything that planes, trains, cars and lorries emit would be put back into the Earth again," explains Branson. These sorts of ideas excite Westwood: "We have to deal with solutions – the actual, the technical and the practical things of what we are going to do. Some bright spark in America said that everyone should paint their roofs white to cool the Earth down. We don't know, but that might be such a simple, brilliant idea."

Simplicity is key to Westwood's ideology: she believes in scaling back the excess and focusing on quality, which sits happily with her label's brand ethic. Her autumn/winter 06 collection featured T-shirts with the motto "I am expensiv" [sic], which she has redesigned in red for Virgin's birthday flight. "There's this picture of a flower on it," she explains. "[It's] got this daft grin because all this consumption is killing it, but we just want more and more. We're just using up the world," she says firmly. "I don't think there's a future in quantity. Every time politicians talk about growth, they're lying. You have to somehow pull back and make only what's useful."

Time was when a Westwood piece was an investment – something ordinary people would save up to buy. But with the onset of fast fashion, such shopping habits have disappeared. And Westwood is happy to say "Don't buy clothes," and to speculate on whether fashion should even exist in a world of such imminent crisis. She wants to know whether Branson is as willing to play down his own business ' interests for the sake of the Earth's. What does he think of the third runway planned for Heathrow?

"If we can replace polluting fuel with clean fuel," he replies, "which I think we can within five years, it make sense to have it. If you hold Great Britain back from progression, you won't have the resources to build clean power stations and so on. It's a balancing act, but my gut feeling is that a third runway makes sense – with conditions of practice: that the planes flying on that runway are not polluting."

Westwood's view is that a third runway would be a "white elephant", as she finds me at baggage reclaim to reassert. "My luxury is to be at home," she says. "I don't want to be a misanthropic recluse, but someone has to do something. I don't care who. What's he called – Gordon Brown: do something!" Westwood recently changed political allegiance from the Labour Party, which she has always supported, to the Conservatives, as she believes it will do more in the climate war. She sees the Tories as the only viable opponents to the Government, which she blames for taking us to war in Iraq rather than taking America or China to task for their carbon emissions and disastrous green track records. "The Government talks about it as if [the climate change issues are] just on its list of things to do instead of a fundamental problem.

"They [Lovelock and Lynas] say that, if the temperature tips over two degrees above pre-industrial levels – above what kept the Earth in equilibrium for millennia – all the animals in the world will die," she explains. "But they don't just go at 2.1 [degrees over], do they? They go before that and then it all kicks in and you can't stop it." She is thumping her leg again. "But I'm being very vague. I got up at 4am today because we did a menswear show yesterday, so I'm waffling and over-tired." Tired perhaps, but tireless nevertheless. In Westwood, Gaia may have found one of her most devoted campaigners. n

The green machine: Environmental difference-makers

Al Gore

Ex-vice-president of the US, environmental activist

The man who came so close to winning the presidency in 2000 is now equally well known for a different campaign trail, his lecture tour addressing global warming, as documented in the Oscar-winning film An Inconvenient Truth. He has since received a Nobel Peace Prize.

James Lovelock

Scientist, author of the Gaia hypothesis

Lovelock's message in books such as The Revenge of Gaia is far from optimistic; One of the first environmentalists not to soften the blow for the public, he wrote in The Independent in 2006: "We will do our best to survive, but... the worst will happen, and survivors will have to adapt to a hell of a climate." European temperatures, he predicts, will rise to levels more usually seen in areas such as Baghdad.

Sir Martin Rees

Astronomer Royal, President of the Royal Society

The celebrated academic issued his "scientist's warning" to the world in 2003 with his book Our Final Hour, which asks whether humans will survive this century. Unlike other doom merchants, he has thought beyond planetary issues, placing the salvation of humanity in the intellectual elite's hands by predicting a possible expansion into space.

Sir David Attenborough

Natural-history writer and presenter

The British icon became the patron of UK charity the Optimum Population Trust this year, which campaigns for sustainable human populations that don't destroy their environment. As he concluded in his 2000 documentary State of the Planet, "We have a responsibility to leave for future generations a planet that is inhabitable by all species."

Daryl Hannah

Actor

Hollywood's most dedicated environmental activist, in 2006 Hannah had to be forcibly removed (left) after chaining herself to a tree on LA's South Central Farm for three weeks to stop authorities bulldozing it. Last month she was arrested for protesting against mountaintop removal in West Virginia. Her weekly videos on handy sustainable energy resources are posted on her blog at www.dhlovelife.com.

Mark Lynas

Author of 'Six Degrees: Our Future on a Hotter Planet'

Lynas's 2007 opus on the effects of global temperature increase blew non-believers' stock retort, "A few more degrees? So what?" out of the water. It chronicles the effects of each degree rise on the planet, until at 6º, "perhaps 90 per cent of species become extinct, rivalling the worst mass extinctions in the Earth's 4.5 billion-year history".

Mike Jones