The effect of moving on breathing

Mujib Rahman, editor of a themed issue of the ICE Transport journal on transport emissions, climate change and air quality, says the more we keep moving, the more difficult it is becoming to breathe.

Transport is a significant contributor to air pollution and greenhouse gas emissions.
Transport is a significant contributor to air pollution and greenhouse gas emissions.

The April 2017 issue of the ICE Transport journal looks at the topic of transport emissions, climate change and air quality, with five high-quality papers on air pollution generated from traffic and transport-related activities.

The transportation sector is the single greatest contributor of carbon dioxide to the earth's atmosphere and is responsible for almost one-quarter of hydrocarbon emissions. Civil engineers will find the papers to be informative and rewarding, widening their knowledge and understanding, connecting with existing policies and practices on air pollution.

City smog

The first paper, 'Transport emissions in Beijing: a scenario planning approach' by Cao et al. (2017) shows how to reduce smog-related air pollutants and carbon dioxide emissions generated by passenger transport systems in the large, complex and unique city of Beijing.

The authors examine the current 'business-as-usual' projection for emissions in Beijing and also the drivers and trends affecting current projections. Following on, they develop alternative scenarios that might help reduce projected emissions significantly, by implementing sustainable transport mitigation measures.

The second paper is on the land-use drivers of transport emissions. Wenban-Smith (2017) demonstrates a relationship between greenhouse gas emissions and land-use.

Policy making

The author highlights that factors that are good for emission management are also good for most other aspects of urban policy, towards improving economic and social well-being. As with any concept, however, its impact will depend on the policies and actions that may flow from it. These two papers could be influential in transport planning.

In the third paper, Li et al. (2017) propose a carbon dioxide trading system to stimulate the adoption of low-emission vehicles. A quantitative model is developed to analyse the influence of such a system on the decisions made by potential buyers of low-emission vehicles.

The authors also suggest how governments could implement a personal carbon dioxide trading policy, to promote cleaner cars for the future. This technical paper will be useful for researchers and practitioners working on reducing emissions from car use.

Dirty diesel

The fourth and fifth papers concern air quality in the railway sector. In the fourth paper, Thornes et al. (2017) report the consequences of diesel engine exhaust and related ambient air pollution in enclosed railway stations where ventilation is often inadequate.

In 2012, the World Health Organization's International Agency for Research on Cancer reclassified diesel engine exhaust and identified this ambient air pollution to be carcinogenic and associated with increased mortality from lung cancer.

The authors conclude with a number of possible interventions to ensure a lower impact from air pollution from stationary diesel trains on public health. This is a timely paper and will be very beneficial for researchers, practitioners and policymakers.

Mode choice

In the final paper, Saxe and Denman (2017) examine changes in travel behaviour associated with ridership on the Jubilee line extension in east London, UK and the resulting impacts on greenhouse gas emissions.

The paper looks at initial changes in mode choice after the line opened in 1999, and ongoing mode share trends through to 2011. The authors establish a relationship between metro accessibility and mode choice, based on a travel demand survey. This paper is a good example of how theoretical models can help to address practical issues.