Taxes 'fail to curb travel CO2'

The Air Passenger Duty is unlikely to deter high earners, scientists say

Current UK green tax plans are unlikely to curb the growth in greenhouse gas emissions from travel, a study says.

High-income groups, whose emissions were twice the national average, would absorb any price increase rather than change their travel habits, it said.

Researchers from Oxford University said the data revealed how socio-economic factors shaped how people travelled.

They said targeted measures, such as personal carbon credits, were more likely to influence people's behaviour.

The findings have been published on the day that the Air Passenger Duty on UK flights is doubled; part of the environmental measures outlined by Chancellor Gordon Brown last December.

In their report, the authors questioned the effectiveness of "moderate" tax hikes: "The most conclusive evidence from this study has been the relationship between income and emissions.

"For example, less direct or modestly used fiscal instruments such as moderate petrol or aviation fuel-price increases are less likely to have an effect on the more wealthy sub-sector of the travelling community."

Highest emitters

They suggest that targeted measures, such as awareness campaigns aimed at high emitters or leisure flights, or personal carbon credits would be more effective ways to curb greenhouse gas emissions.

The transport sector contributes 26% of UK carbon emissions and is the only major sector in which emissions are predicted to rise until 2020 Professor John Preston Project leader Air tax rise takes effect

The team, from the university's Centre for the Environment, found that the average climate change impact of an individual's annual travel was equivalent to five-and-a-quarter tonnes of carbon dioxide (CO2).

The highest emitters were mostly men who earned more than £40,000 a year - they were responsible for 19.2 tonnes of CO2 from flights alone.

Looking at all modes of transport, the study showed that air travel accounted for 70% of the sector's climate change impact, while cars were responsible for 25%, and public transport for 3.5%.

Project leader John Preston said that the percentages represented "climate change impact", not CO2 emissions, because the study took into account "positive radiative forcing", which refers to evidence that CO2 emissions from aircraft at high altitudes are more potent than CO2 released at ground level.

"That is part of the reason why we come up with a much bigger figure for emissions from aviation than is often quoted by the aviation industry, which tends not to include radiative forcing," he explained.

The research, funded by the Economics and Social Research Council (ESRC), was based on a survey of almost 500 people in Oxfordshire, which included postal and web-based questionnaires and face-to-face interviews.

Professor Preston said the findings also gave a useful indication of the UK's travel habits.

"We did compare our data to national surveys, such as the National Travel Survey, and our sample is reasonably representative of the nation as a whole."

He added that the UK was facing tough choices on the most effective way to lower greenhouse gas emissions.

"The transport sector contributes 26% of UK carbon emissions and is the only major sector in which emissions are predicted to rise until 2020. Transport is thus a priority area for government policy."