Which is worse for the environment – cars or aircraft? If your answer was aircraft, then you are among a growing crowd of aerophobes egged on by anti-aviation campaigners.

But in terms of CO2 emissions you would be wrong. Official figures show an increase in the number of people duped into believing that flights are more damaging than car journeys.

The number of people who think that flying contributes more to climate change than car journeys has risen rapidly in the past 18 months, coinciding with a rise in activity by groups opposing any increase in air travel.

In the National Statistics omnibus survey, conducted in August 2006, 39 per cent of people thought that cars were the most environmentally damaging mode of transport, while 35 per cent selected planes. When the same question was asked in August 2007 cars had slipped to 34 per cent and planes had risen to 40 per cent.

Estimates from the Department for Transport for 2005 show that cars emitted 69.9 million tonnes of CO2 while domestic and international aviation emitted 37.5 million tonnes.

The survey found that almost half the population (47 per cent) believed that air travel should be limited for the sake of the environment. Only 23 per cent supported making it more expensive as a way of reducing emissions.

The proportion of people who said that they were likely to fly less often in the next 12 months rose from 12 per cent in 2006 to 15 per cent last year.

The most popular option for reducing emissions was to increase public spending on buses, supported by 60 per cent of people, and increasing spending on trains (56 per cent).

Young people were much less likely to be concerned about climate change than middle-aged people. Among 16 to 24-year-olds 69 per cent said that they were very or fairly concerned compared with 86 per cent of people aged 45 to 54. People living in London were more worried about climate change than those in any other region.

People were also twice as likely to trust environmental groups to tell them the truth about climate change as they were the Government.

The latest survey was conducted after publicity about the “climate camp” organised by antiaviation protesters at Heathrow.

Enoughsenough, a green group funded mainly by anonymous individuals, has spent hundreds of thousands of pounds in the past 18 months on advertisements attacking the aviation industry for damaging the climate.

Michelle Di Leo, the director of Flying Matters, which lobbies for airport expansion, said: “When antiaviation groups are allowed to set the agenda it can result in policy being distorted.

“Raising the cost of air travel disproportionately affects families on low incomes who may not be able to afford to fly,” she added, referring to the government decision last year to double air passenger duty.

Jeff Gazzard, of the Greenskies Alliance, which is opposed to growth in air travel, said: “We shouldn’t be worried by the misapprehension. People exaggerate the contribution of air travel because they see flights as discretionary whereas driving is an everyday thing they can’t do without.”

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