For the apparently benign escapism of air travel is emerging as one of the greatest threats to the future of the planet. It is the fastest growing source of the pollution that causes global warming. A planned new generation of aircraft, as revealed on page 1, imperils the ozone layer that shields all life from the sun's deadly ultraviolet rays. And airports outdo almost all factories as sources of dangerous pollution – while the noise from planes blights millions of lives.

And yet it is treated with unparalleled indulgence. Taxing its fuel is banned by international treaty, giving it a unique encouragement to pollute. Emissions from international flights are excluded from the treaties agreed to combat global warming and ozone depletion. Airports in Britain are exempt from pollution control, from getting planning permission for many developments, and – in most cases – from statutory noise regulation. And, to top it all, air travel receives billions of pounds every year in subsidies from the taxpayer.

Air travel is climbing up the political agenda. Ministers are soon to decide on whether to give the go-ahead to a fifth terminal at Heathrow. Concorde is expected to take to the air again before the swallows fly out at the end of the summer. And, most important of all, the Government will publish a White Paper next year setting out aviation policies for the next three decades. So far, there is little sign of any change in the traditional governmental view that the rapid growth of air traffic is an almost unmitigated good. The public debate that has long raged over increasing traffic on the roads has yet to reach for the skies.

The fastest growing form of transport worldwide is air travel. It has soared a hundredfold in the last 50 years, and is expected to multiply 10 times more in the next half century. Meanwhile, the number of passengers passing through British airports has risen five-fold since the mid-1970s, and is expected to more than double again by 2020. We are flying further, as well as more often, as long-haul holidays become ever more popular. Latin America is this year's fashionable destination: Tony Blair's holiday in Mexico seems another case of his flair for catching a trend. Over the past few years, according to the British Airports Authority, there have been similar surges in travel to India, Sri Lanka, Australia and the Far East.

The growth of cheaper flights has produced great benefits, bringing the world within pocket-book range of most Britons, making it possible to visit far-flung friends and relatives – while bringing an ever-wider variety of goods into the shops. But as a report published this month by the Institute of Public Policy Research (IPPR) says, "flying by jet plane is the least environmentally sustainable way to travel and transport goods".

Take global warming. Aircraft pump out carbon dioxide and other greenhouse gases high in the atmosphere, where they do more damage. The official Intergovernmental Panel on Climate Change calculates that they are responsible for at least 3.5 per cent of global warming, equivalent to the emissions from the whole of Canada. And this is only the start: estimates of their contribution by the middle of the century range from 10 to 17 per cent.

True, the industry has cut the amount of fuel it burns to transport each of its passengers by half since the mid-1970s. But this has been far outweighed by the growth of air traffic. The International Civil Aviation Authority is to examine what more can be done to fight global warming at its annual meeting next month. But the exemption given to international flights by the Kyoto Protocol, and the unique ban by the 1944 Chicago Convention on taxing fuel, remove incentives for adequate improvement.

It is the same story with other pollutants. The industry has sharply cut emissions of nitrogen oxides and hydrocarbons from each plane, but again increasing numbers have outpaced the reductions. And aircraft are only part of the problem, for airports also emit massive air pollution from refueling and storing fuel, from maintenance and supply operations, and from the huge amount of road traffic they generate. Research shows that JFK airport is the biggest nitrogen oxides polluter in New York, and that Frankfurt airport contributes nearly three-quarters of its city's emissions of unburnt hydrocarbons and almost half its load of pollution by carbon monoxide, sulfur dioxide and nitrogen dioxide. And, if Terminal 5 is built, Heathrow will emit Britain's second highest amount of volatile organic compounds, many of which cause cancer, after a factory on Teesside.

Ominously, a US government study has found that pollution from aviation has increased rates of cancer around Chicago-Midway airport, about the same size as Gatwick. Yet, scandalously, British airports escape all pollution control, falling outside the jurisdiction of the Environment Agency and of local authorities. Noise, too, is largely unregulated. Only Heathrow, Gatwick and Stansted airports are subject to statutory control, though ministers are now drawing up proposals to strengthen regulation. Although individual planes are getting quieter, noise is also increasing with the number of flights.

Though the authorities have tried to underplay its impact, the European Environment Agency last year concluded that 440,000 people around Heathrow are plagued with noise above the standards set down by the World Health Organization. Excessive noise damages health, with effects ranging from hearing damage to heart disease. And it blights children's education. Studies around Munich airport and New York's La Guardia and JFK conclude that it impairs their memory and reading ability.

Meanwhile, the economic benefits of increased air travel, long cited as the justification for its expansion, are looking uncertain with new studies, including one by Transport 2000, undermining old assumptions. And what remains is undermined by vast subsidies such as untaxed fuel, duty-free sales, relief on landing charges and official loans. The IPPR study says these are worth £6bn a year in Britain.

Solutions are hard to find. Fast rail services can replace some short-haul flights, but experience in Germany and from the Channel Tunnel shows these just free up slots for more long-haul ones. Information technology could reduce the need for business travel, but could also increase it by encouraging more international projects.

Subsidies must be ended, aircraft fuel taxed, and exemption from pollution control ended. New charges can be levied on polluting aircraft, as has been done in Switzerland, and on all flights, as in Denmark. But these will only slow, not stop the explosive growth of air travel. Reducing its increasingly devastating impact on the planet would require a reversal of one of the most liberating trends of the last half century. And this bank holiday weekend that's about as likely as pigs taking wing.

© 2001 Independent Digital (UK) Ltd

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