The arrogance of these elitist shysters trying to perpetrate a fraud on the people.

On a normal day, Majken Friss Jorgensen, managing director of Copenhagen's biggest limousine company, says her firm has twelve vehicles on the road. During the "summit to save the world", which opens here tomorrow, she will have 200.

"We thought they were not going to have many cars, due to it being a climate convention," she says. "But it seems that somebody last week looked at the weather report."

Climate Express sets off for Copenhagen Ms Jorgensen reckons that between her and her rivals the total number of limos in Copenhagen next week has already broken the 1,200 barrier. The French alone rang up on Thursday and ordered another 42. "We haven't got enough limos in the country to fulfil the demand," she says. "We're having to drive them in hundreds of miles from Germany and Sweden."

And the total number of electric cars or hybrids among that number? "Five," says Ms Jorgensen. "The government has some alternative fuel cars but the rest will be petrol or diesel. We don't have any hybrids in Denmark, unfortunately, due to the extreme taxes on those cars. It makes no sense at all, but it's very Danish."

The airport says it is expecting up to 140 extra private jets during the peak period alone, so far over its capacity that the planes will have to fly off to regional airports – or to Sweden – to park, returning to Copenhagen to pick up their VIP passengers.

As well 15,000 delegates and officials, 5,000 journalists and 98 world leaders, the Danish capital will be blessed by the presence of Leonardo DiCaprio, Daryl Hannah, Helena Christensen, Archbishop Desmond Tutu and Prince Charles. A Republican US senator, Jim Inhofe, is jetting in at the head of an anti-climate-change "Truth Squad." The top hotels – all fully booked at £650 a night – are readying their Climate Convention menus of (no doubt sustainable) scallops, foie gras and sculpted caviar wedges.

At the takeaway pizza end of the spectrum, Copenhagen's clean pavements are starting to fill with slightly less well-scrubbed protesters from all over Europe. In the city's famous anarchist commune of Christiania this morning, among the hash dealers and heavily-graffitied walls, they started their two-week "Climate Bottom Meeting," complete with a "storytelling yurt" and a "funeral of the day" for various corrupt, "heatist" concepts such as "economic growth".

The Danish government is cunningly spending a million kroner (£120,000) to give the protesters KlimaForum, a "parallel conference" in the magnificent DGI-byen sports centre. The hope, officials admit, is that they will work off their youthful energies on the climbing wall, state-of-the-art swimming pools and bowling alley, Just in case, however, Denmark has taken delivery of its first-ever water-cannon – one of the newspapers is running a competition to suggest names for it – plus sweeping new police powers. The authorities have been proudly showing us their new temporary prison, 360 cages in a disused brewery, housing 4,000 detainees.

And this being Scandinavia, even the prostitutes are doing their bit for the planet. Outraged by a council postcard urging delegates to "be sustainable, don't buy sex," the local sex workers' union – they have unions here – has announced that all its 1,400 members will give free intercourse to anyone with a climate conference delegate's pass. The term "carbon dating" just took on an entirely new meaning.

At least the sex will be C02-neutral. According to the organisers, the eleven-day conference, including the participants' travel, will create a total of 41,000 tonnes of "carbon dioxide equivalent", equal to the amount produced over the same period by a city the size of Middlesbrough.

The temptation, then, is to dismiss the whole thing as a ridiculous circus. Many of the participants do not really need to be here. And far from "saving the world," the world's leaders have already agreed that this conference will not produce any kind of binding deal, merely an interim statement of intent.

Instead of swift and modest reductions in carbon – say, two per cent a year, starting next year – for which they could possibly be held accountable, the politicians will bandy around grandiose targets of 80-per-cent-plus by 2050, by which time few of the leaders at Copenhagen will even be alive, let alone still in office.

Even if they had agreed anything binding, past experience suggests that the participants would not, in fact, feel bound by it. Most countries – Britain excepted – are on course to break the modest pledges they made at the last major climate summit, in Kyoto.

And as the delegates meet, they do so under a shadow. For the first time, not just the methods but the entire purpose of the climate change agenda is being questioned. Leaked emails showing key scientists conspiring to fix data that undermined their case have boosted the sceptic lobby. Australia has voted down climate change laws. Last week's unusually strident attack by the Energy Secretary, Ed Miliband, on climate change "saboteurs" reflected real fear in government that momentum is slipping away from the cause.

In Copenhagen there was a humbler note among some delegates. "If we fail, one reason could be our overconfidence," said Simron Jit Singh, of the Institute of Social Ecology. "Because we are here, talking in a group of people who probably agree with each other, we can be blinded to the challenges of the other side. We feel that we are the good guys, the selfless saviours, and they are the bad guys."

As Mr Singh suggests, the interesting question is perhaps not whether the climate changers have got the science right – they probably have – but whether they have got the pitch right. Some campaigners' apocalyptic predictions and religious righteousness – funeral ceremonies for economic growth and the like – can be alienating, and may help explain why the wider public does not seem to share the urgency felt by those in Copenhagen this week.

In a rather perceptive recent comment, Mr Miliband said it was vital to give people a positive vision of a low-carbon future. "If Martin Luther King had come along and said 'I have a nightmare,' people would not have followed him," he said.

Over the next two weeks, that positive vision may come not from the overheated rhetoric in the conference centre, but from Copenhagen itself. Limos apart, it is a city filled entirely with bicycles, stuffed with retrofitted, energy-efficient old buildings, and seems to embody the civilised pleasures of low-carbon living without any of the puritanism so beloved of British greens.

And inside the hall, not everything is looking bad. Even the sudden rush for limos may be a good sign. It means that more top people are coming, which means they scent something could be going right here.

The US, which rejected Kyoto, is on board now, albeit too tentatively for most delegates. President Obama's decision to stay later in Copenhagen may signal some sort of agreement between America and China: a necessity for any real global action, and something that could be presented as a "victory" for the talks.

The hot air this week will be massive, the whole proceedings eminently mockable, but it would be far too early to write off this conference as a failure.