Policymakers must address urgently the rapid rise in personal air travel if they wish to reduce CO2 emissions, warn researchers from the Transportation Research Group at Southampton University and the Environmental Change Institute at Oxford University. Their 'Integrated Travel Emissions Profiles' project investigated greenhouse gas emissions and related climate change impacts from transport at the personal, household and local levels. "We were surprised to find that, with respect to the effect of personal travel on climate change, air travel is much more damaging than we had previously thought," says researcher Professor John Preston.
Based on a study of travel activities over a 12-month period of more than 450 individuals living in Oxfordshire, researchers were able to calculate total annual personal travel emissions of CO2 and other greenhouse gases. The findings reveal that air travel is responsible for 70 per cent of passenger transport climate change impacts at the individual level. Car travel, in contrast, accounts for some 25 per cent of an individual's transport-related CO2 impact on the environment.
"To date, many government policies to reduce travel CO2 emissions have been focused on car travel and rightly so," Professor Preston points out. "But, as this study shows that personal air travel is three times as damaging as car travel, then policies should address this imbalance. Instead,current policies are encouraging the increase in air travel through continuously low air fares and airport and runway expansion schemes."
A second significant finding of this study is the very uneven distribution throughout the population of the damage done to the climate through personal travel. "The startling fact is that while a large proportion of the population produce similar travel and greenhouse gas emissions profiles, a few are responsible for a disproportionately large share of the total," he explains. In this study, the top ten per cent of travel polluters were responsible for some 43 per cent of climate change impact. "The clear implication is that government policies should target the relatively small number of people who are responsible for the worst emissions excess rather than apply blanket policies to everybody," he states.
In terms of policies, a carbon tax on aviation fuel would appear warranted. But, Professor Preston admits, this would be a difficult tax to operate in practice without EU-wide support as plane operators would simply refuel in countries with no tax.
"The main alternative to pricing is a scheme called 'personal carbon allowances', which has gained much interest among researchers and Government alike," he points out. "Under personal carbon allowances, emissions would be limited for each person in the UK, and we could 'spend' carbon, save it and trade it in the same way we do with money. As this covers all personal greenhouse gas emissions, including air and car travel, household electricity use and heating, it would be up to us how to spend and save carbon. There is a huge range of imponderables and a huge range of technical questions about feasibility. But we need to test other policy answers against the most radical options if we are to make the progress needed to reduce our climate change impact and avoid dangerous climate change."
Award number: RES-000-22-0564