A recent study revealed that airlines are spewing 20% more CO2 into the atmosphere than previously suggested, with total emissions set to reach between 1.2 billion and 1.5 billion tons per year by 2025.

The airline industry has tackled a lot of heat lately concerning its soaring carbon emissions. According to the United Nations, its failure to implement significant reductions could lead to the “worst case scenario” for climate change. A recent study revealed that airlines are spewing 20% more CO2 into the atmosphere than previously suggested, with total emissions set to reach between 1.2 billion and 1.5 billion tons per year by 2025.

This data was produced by the leading emissions-modelling laboratories in the US, Britain and France, and presented to a conference co-organized by the United States’ Federal Aviation Authority.

The study also found that the number of people seriously affected by aircraft noise will rise from 24 million in 2000 to 30.3 million by 2025, despite the introduction of quieter jets, and that the amount of nitrogen oxides around airports, produced by aircraft engines, will rise from 2.5 million tons in 2000 to 6.1 million tonnes in 2025.

Jeff Gazzard, a spokesman for the Aviation Environment Federation, the group that uncovered the report, said: “Growth of CO2 emissions on this scale will comfortably outstrip any gains made by improved technology and ensure aviation is an even larger contributor to global warming by 2025 than previously thought. Governments must take action to put a cap on air transport’s unrestrained growth.”

The report, Trends in Global Noise and Emissions From Commercial Aviation for 2000 through 2025, was presented last year to the USA/Europe Air Traffic Management Seminar in Barcelona but withheld from wider publication.

Its authors at the US Department of Transport, the European air traffic management body, Eurocontrol, Manchester Metropolitan University and the technology company QinetiQ predict that CO2 will rise from its current level of 670 million tonnes to up to 1.48 billion tons by 2025. This exceeds the previous estimate, made in 2004, of 1.03 billion tons by 2025. The growth in aviation CO2 means that the highest forecast for aviation emissions produced by the International Panel on Climate Change will be met or exceeded.

The aviation industry, which is exempt from the Kyoto protocol on reducing greenhouse gases, claims the introduction new technology over the next 25 years means that the contribution of flying to global CO2 emissions will rise from 2 per cent of the total to 5 per cent by 2050. Critics claim the true figure will be much higher because it does not include the CO2 reductions being made elsewhere.

The International Air Transport Association, which represents 240 airlines, said it was working towards producing binding targets to reduce CO2 emissions. “With fuel costs doubling in the last year, airlines already have an incentive to work towards greater efficiency,” a spokesman said. “There has been a 70% improvement in fuel efficiency in the last four decades. Aviation is a benchmark of environmental responsibility for others to follow.”