But not this year. Staring out over her rolling fields of corn, Anita Hoffhines was puzzled. There had been no real need this winter for her family's ample supply of snow shovels. The vast drifts of snow that bury the prairies for months on end had not come. 'The climate is getting warmer. You can just feel it,' she says. Even here, in America's small-town heartland, where the politics are red and the cars are huge, everyone is talking about global warming.

That is at odds with the usual outsiders' impression of America under President George W Bush. The US and the current occupant of the White House are the bugbears of environmentalists. Bush refused to sign the Kyoto protocols limiting carbon emissions, yet America is the world's largest producer of them. Bush's reason was simple and self-serving: American jobs needed to be saved. At the same time, as a former oil man, he is close to his old industry, which provided millions of dollars in campaign contributions. Only last month Bush paved the way for oil exploration in an Alaskan wilderness that had long been a cause célèbre for America's conservationists. The image of an Emperor fiddling while Rome burns has been hard to resist.

Yet that image is wrong. The White House may not be changing, but much of the rest of America is. Beneath the surface a quiet green revolution is taking place in American politics, and, perhaps more importantly, in American business. Bush is often accused of being out of touch with the rest of the world when it comes to climate change. He might just be out of touch with the American people, too. 'We are reaching a tipping point in America,' says an unexpectedly optimistic Hans Verolme, director of the US climate change programme at the World Wildlife Fund.'In the last year we have made tremendous progress.'

ON THE surface it seems as bad as ever. America's love of the big car, as exemplified by the sight of Hummers barrelling down the country's freeways, is as passionate as ever. Many Americans' main outrage of the moment is not global warming but high petrol prices. When petrol rose above $2 a gallon this year Americans howled, but few realise that such a price in Europe would be seen as derisively cheap.

There are also high-profile deniers of climate change in popular culture. Michael Crichton, author of Jurassic Park, attacked the environmental movement in his latest book, State of Fear. Crichton portrayed climate change as being vastly exaggerated by self-serving scientists. The real threat to the earth were environmentalists, not greenhouse gases, he said. The book was a bestseller.

Some high-profile American scientists agree. When the Senate recently debated climate change, one senator, Republican James Inhofe, called global warming a hoax. His words were based partly on the work of climatologist John Christy, director of the Earth System Science Center at the University of Alabama. Christy is a respected scientist and forthright in his views. He says advancing human technology will sort out any climate change issues, not measures that will cost businesses money. 'In general I agree with the administration. Technology will improve along a path that will eventually solve emission of carbon gases,' he says.

The Bush administration has shown a keen instinct for the political implications of global warming, but not the environmental ones. Many pieces of legislation seem to have an Orwellian feel, with high-sounding names betraying an anti-environment agenda. The Clean Air Act has been attacked as actually aiding polluters and providing a raft of benefits to big oil and coal firms. The Healthy Forests law opened up millions of acres of previously protected land to logging firms. The administration has also attacked scientists who have spoken out on climate change and suppressed information that it did not agree with.

One of the most shocking incidents was the legal fight waged by Vice-President Dick Cheney to keep under wraps details of how White House energy policy was formed. Cheney had appointed an 'Energy Task Force', stacked full of oil and energy industry executives, to draw up energy legislation. He successfully fought off all legal challenges to publish minutes from their meetings. He finally won in the Supreme Court, though not until after it emerged that Cheney had been duck-hunting with one of the judges on the case at an estate owned by an oil baron.

There is certainly little doubt that the energy industry enjoys great influence in the White House, partly because of the huge amounts it donates to Republican party coffers. Bush's top campaign donors are dubbed Pioneers and Rangers for raising $100,000 and $200,000, respectively, for the party. Many are energy executives. Dwight Evans, a vice-president at Southern, was a Pioneer in the 2004 Presidential election and had numerous contacts with Cheney's task force. Erle Nye, chairman of TXU, was another 2004 Pioneer and task force member. There are many others.

BUT that is only part of the story now. Across America things are changing. Led by Seattle's Democratic mayor Greg Nickels, at least 131 city mayors have vowed to implement the Kyoto protocol in their own towns. Added together they represent 29 million citizens in 35 different states. That makes the grouping bigger than many entire countries that have signed up to Kyoto.

What is more, many of the cities are led by Republicans and some come from the most conservative parts of the country, such as the town of Hurst in deepest Texas. The latest addition to the club is New York, which has been signed up by its Republican mayor, Michael Bloomberg.

The revolt against administration policies has even spread right into the heart of the Republican party's own base, its powerful evangelical Christian wing. Earlier this year 1,000 church leaders and other clergy signed a powerful statement calling on the White House to act on environmental issues, including global warming.

Dubbed 'Creation Care' the movement is highly significant as evangelicals were the key force in securing Bush's electoral victory last year. They make up about 40 percent of the Republican party voter base. But their statement pulled no punches in attacking the White House. 'There was no mandate, no majority, or no "values" message in this past election for the President or the Congress to roll back and oppose programmes that care for God's creation,' the statement said.

The huge religious lobbying group, the National Association of Evangelicals, which represents about 30 million Christians, has also adopted a resolution that defined caring for a sustainable environment as a part of every Christian's duty. Bush, whose own religious faith is as devout as his political instinct is sharp, will certainly have paid full attention to all the implications of that message.

In fact, Kyoto, or measures that closely match the agreement in terms of cutting carbon emissions, are steadily creeping across the country. It is also a movement being led by Republicans. New York state, where the governor is Republican George Pataki, announced in May that it would adopt a series of tough rules on cutting greenhouse gases from cars and other motor vehicles. Pataki is also leading a regional coalition of 10 north-eastern American states looking at ways of co-operating on cutting down on carbon emissions.

A similar story is unfolding in California, which is led by another Republican governor, former movie star Arnold Schwarzenegger. The state already has stricter emission controls that many other American states, but Schwarzenegger is now aggressively pushing plans to develop hydrogen-fueled cars whose exhausts emit only water. He recently announced the spending of $54 million to help build a network of up to 100 hydrogen fueling stations state-wide within five years.

But, crucially, attitudestowards climate change have shifted in big business, too. Many large US companies have turned from opposing plans to control carbon emissions to embracing them. In part this reflects a hard-headed business attitude.

'They believe that some sort of carbon emission control is inevitable so it is better to get rid of the uncertainty. Many of them now want legislation to come in sooner rather than later,' said David Doniger, climate centre policy director at the National Resources Defence Council 'The whole focus of lobbying in Washington has changed from trying to keep legislation out to trying to shape it when it comes.'

Certainly the noises coming from American big business leaders on climate change have been remarkably stark recently. Jeff Immelt, boss of iconic US firm General Electric, recently committed the firm to a set of green goals going far beyond any current government regulations. He even attacked America's 'do-nothing' policy on climate change.

That has been followed by Cinergy, a power firm with huge coal interests, which has been touting its takeover of a rival company partly on the basis that the resultant cost-cutting will allow Cinergy to slash carbon emissions. Again, the rationale is simple business logic.

Many American firms with partners in Europe, which has signed up to Kyoto, are already bound by its rules when they do business there. They are also wary of being held responsible for future liabilities if they do not act now, in the same way tobacco firms and asbestos producers have been hit. All of a sudden the curious marriage of big business and environmentalism is not looking so strange after all. It is looking like common sense.

Soon the White House itself might catch up. Chuck Hagel is a Republican Senator who has already positioned himself as one of the leading contenders for the Presidential election in 2008. He is from Nebraska, one of the true strongholds of conservative Republicanism. Yet in a speech delivered to the Brookings Institution think-tank in February, Hagelannounced plans to introduce three separate bills aimed at curbing carbon emissions. He was adamant in his belief that climate change is occurring. Then, stunning many commentators, he damned the current White House policy on the issue. 'We have been out of the game for four years. That is dangerous. It's irresponsible and we need to address it,' he said.