LONDON (AP) -- Britain should drastically reduce the growth of air travel to bring greenhouse gas emissions within levels that will avoid dangerous climate change, a report by leading environmental scientists said Wednesday.
Air travel has boomed in recent years, thanks largely to cheaper flights, and the government predicts that the number of air passengers in Britain will more than double by 2020. But aviation is a major source of carbon dioxide, the main greenhouse gas, because planes burn huge amounts of fossil fuels at high altitudes.
The government says it wants a 60 percent cut in carbon dioxide emissions by 2050, compared with 1990 levels, as the nation's contribution toward preventing an increase in temperatures that would threaten a dangerous level of climate change.
But the Tyndall Center for Climate Change Research, which includes scientists from universities across Britain, said that target is incompatible with the current expansion rate of the aviation industry.
''If aviation continues to grow at its current rate, then it won't be possible to meet the 60 percent targets unless we all massively reduce our consumption of energy in other ways,'' the Tyndall Center's Simon Shackley told The Associated Press.
The report said slashing emissions from other sectors to almost zero would severely hamper Britain's economic growth.
Instead, the Tyndall Center report, ''Decarbonizing the United Kingdom,'' urged improvements in energy efficiency and the use of low-carbon sources of energy _ such as wind power, solar energy, hydrogen and nuclear power. It said these measures would be compatible with economic growth.
Aviation, however, is much more difficult to decarbonize with currently available technology, so growth in the sector must be ''dramatically curtailed,'' the report said.
Current government predictions suggest the number of air passengers will grow from 189 million in 2002 to between 350 and 460 million in 2020.
Shackley said measures to restrict the air industry's expansion might include a carbon trading scheme, in which every person would have an annual carbon output allowance. Those who have a surplus would be able to trade it with those seeking to go beyond their allowance.
Environment Minister Elliot Morley said he accepted the need to reduce emissions, but opposed a tax on aviation fuel, something green campaigners have pressed for. Currently, airlines pay no tax on fuel.
''The evidence is that people will simply pay the tax and continue to travel and we won't actually stop the growth,'' Morley told British Broadcasting Corp. TV.
''I actually think there are other ways of doing it. The most effective one is to include aviation within carbon trading schemes, so there is an absolute limit on the amount of emissions from the aviation sector.''
Britain is pressing for aviation to be included in the second phase of the EU Emissions Trading Scheme, which begins in 2008, according to the Department for Environment, Food and Rural Affairs.
Under the plan, European companies that emit less carbon dioxide than permitted are allowed to sell unused allotments to those who overshoot the target.
Environmental pressure group Friends of the Earth, however, said it favored an aviation fuel tax.
''The Department of Transport's own models on aviation growth show dramatic reductions in air travel when assumptions are added for fuel taxes and other factors,'' the group's director Tony Juniper said in a statement.
''Aviation is a rogue sector and its environmental impact is out of control,'' he said. ''Climate change is the most urgent challenge facing humanity and yet aviation policy is doing the opposite of what is needed.''
Copyright 2005 Associated Press
