Changing the way we live…

Commercial flights began to be both profitable and popular in the 1930s, with the arrival of the propeller-powered Douglas DC-3. The western world has since been transformed by the possibility of travelling quickly to places that our ancestors had barely heard of, along with the possibility of air-lifting food and other goods from distant parts.

But today’s Europeans are worried that all those aeroplanes might be changing the world in a different, less positive way. The aviation sector is estimated to contribute annually emissions of 700 million tonnes of carbon dioxide (CO2), the greenhouse gas most closely linked to global warming.

Airline fuel is untaxed in Europe, an exemption environmentalists say is particularly egregious given that aviation emissions are not counted against efforts to reduce EU emissions under the Kyoto Protocol on climate change.

In December the European Commission proposed making airlines buy and sell CO2 emission permits from each other. This extension of the EU Emission Trading Scheme (ETS) would see less polluting airlines benefiting financially from ‘dirtier’ companies. The Council of Ministers and the European Parliament have yet to give their opinions.

Perhaps aviation’s best defence against global warming charges, ironically, comes from the Intergovernmental Panel on Climate Change (IPCC). The same UN scientific organisation that on 2 February increased the pressure for international action on climate change, by saying temperatures were rising faster than previously thought, has also famously put aviation’s contribution to global CO2 emissions at just 2%. The IPCC adds that by 2050 this is unlikely to have risen to more than 3%. CO2 emissions from buildings today make up around 13% of the world total.

Critics point out that the findings come from a 1999 report, which was itself based on 1992 data. More importantly, the 2% figure ignores the ‘multiplier effect’ which must be applied to aviation emissions.

A multiplier is needed to calculate the total climate change impact of aviation. Other greenhouse gas emissions such as nitrogen oxides (NOx) are also produced by aeroplanes and the aviation-induced formation of cirrus clouds also affects the climate on earth.

A study from environmental group Transport and Environment (T&E) says that aviation’s contribution to climate change could be up to five times that of the CO2 emissions alone. It adds that "the rapid growth of aviation and aviation emissions" means the situation has changed drastically since the IPCC report appeared seven years ago.

But Anthony Concil from the industry group the International Air Transport Association (IATA) says he expects the IPCC to stand by its old figures in an updated report, due sometime after April.

CO2 emissions from aviation will still be shown to remain at 2% of the global total, with 3% estimated for 2050, he predicts.

"And scientists are now increasingly saying the multiplier effect is coming down," Concil adds. "I think the IPCC will say the multiplier effect is much slower than previously thought."

According to IATA, emissions trading is not the only way the EU can cut aviation’s climate change impact. If Europeans really want to cut emissions, says Concil, they should agree a deal on currently stalled proposals for a ‘single European sky’.

"More direct routing, less holding time and fewer delays could mean 12 million tonnes less CO2 a year from flights over Europe," he says.

Commercial flights began to be both profitable and popular in the 1930s, with the arrival of the propeller-powered Douglas DC-3. The western world has since been transformed by the possibility of travelling quickly to places that our ancestors had barely heard of, along with the possibility of air-lifting food and other goods from distant parts.

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