Let’s place more focus on long-distance travel emissions

New research from the University of Leeds suggests that the impact of long distance travel (a one-way journey over 50 miles) is being overlooked, as the emphasis continues to be lowering the number of short distance journeys in towns and cities.

Only 3% of all trips by UK residents fall into the long distance category but they are responsible for 70% of all passenger travel carbon emissions. Furthermore, only 0.4% of those trips involve leaving the UK but are responsible for 55% of emissions.

The implication is that long distance travel is the low-hanging fruit in reducing emissions.  Most strategies currently in place, such as low emissions zones, improving public transport and making it easier to walk and cycle are aimed at reducing the number of short-range journeys made, yet there are simply so many such journeys that, as the report points out, very large-scale changes in these trips are needed for these policies to make a substantial dent in emissions.

Dr Zia Wadud from the University’s Institute for Transport Studies and School of Chemical and Process Engineering and who led the research, said: ‘The scale of the impact of long-distance travel is very large indeed. That just less than 3% of our trips are responsible for around 60% of miles and 70% of emissions shows how important long-distance travel is in the fight to combat climate change.

‘Worryingly, long distance trips, especially flights, have been growing; however, they offer opportunities too.’

The team created a new metric: emission reduction sensitivity, to determine which types of travel could be changed to maximise a reduction in carbon emissions from passenger travel whilst affecting as few people or trips as possible.

The ERTSA (emissions reduction sensitivity with respect to trips altered) score calculates the ratio of percentage changes in emissions to percentage alterations in the trips.

For example, if all car journeys under eight miles were walked or cycled, there would be a 9.3% reduction in carbon emissions. However, 55% of all journeys fall into this category, because most travel is over short distances and in cars. The ERTSA score for this change would be just 0.17 – the lowest recorded in the study.

A better result would be if all flights of less than 1,000 miles were made by train instead. This  would see a 5.6% reduction in emissions while only 0.17% of journeys would be affected – resulting in a ERTSA score of 33.2.

At the top end, limiting everyone who currently flies to just one return flight abroad per year would have a value of 158.3, as so few journeys would be affected.

Dr Muhammad Adeel, a co-author now at the Centre for Transport and Society at the University of the West of England, said: ‘Whilst efforts to move local journeys to more sustainable modes of transport are really positive, by omitting aviation emissions from national statistics – as is the case at the moment in nearly all countries – we are not getting a holistic picture and ignoring a large part of the problem.’

Dr Wadud added: ‘The important thing both at the policy and personal level is that we prioritise the relatively fewer longer distance trips – especially flights – in order to realize the largest reductions.’

The full report can be read here