Air pollution has a significant negative impact on public health and is something that affects most of us, every day. In large cities, such as Beijing and London the problems can be more obvious, but mostly it remains an invisible danger.
Quantifying the impacts of air pollution is extremely difficult. In 2010, the UK Department of Health’s Committee on the Medical Effects of Air Pollutants (COMEAP) reported that long-term exposure to outdoor air pollution caused the equivalent of approximately 29,000 UK deaths in 2008.
Even more worryingly, in 2016, a Royal College of Physicians report suggested the annual figure could be closer to 40,000 deaths, and the World Health Organization (WHO) reported the adverse impact on public health caused by pollution costs the UK economy more than £50 billion per year.
Significant stationary pollutant sources are associated with industrial and energy production, along with other combustion processes and agriculture. However, given the increasing global urban population, estimated by the UN to reach 60% by 2030, transport emissions (specifically, nitrogen dioxide and particulate matter) are the most significant source of air pollution affecting human health.
Understanding, measuring, modelling and predicting air pollution is complex. Urban pollution episodes can occur around calm, dry, settled conditions allowing pollution to build-up around busy roads; or episodes can be caused by long-range transportation of pollutants from sources thousands of miles away, such as volcanic eruptions, Saharan dust or forest res. Urban geography has a part to play too with street canyons recirculating and trapping pollution, and steeper hills requiring greater vehicular acceleration, creating more harmful pollution.
What’s being done?
In recognition of the scale of the problem, governments worldwide are committed to more rigorous air quality regulation and monitoring, reducing transport emissions by supporting the uptake of low and zero emission fuels and technologies, reducing the volume of heavily polluting vehicles, promoting a modal shift away from the car through active travel, designing urban spaces to reduce pollution, and reducing the need to travel.
Intelligent Transport Systems (ITS) have the opportunity to be instrumental in meeting air quality challenges. In order to efficiently manage air quality and reduce exceedances of air quality standards, it is necessary to be able to accurately monitor and predict the concentrations of harmful road traffic pollutants within the air in real-time.
A project I have been involved in with Transport Scotland examined this concept; testing new, lower-cost air quality monitoring equipment, deploying it at various roadside locations, then analyzing the data in parallel with traffic and meteorological data. The ultimate goal is to develop a system to gather and integrate air quality and traffic data from multiple sources, and build this into a decision support tool to model, predict, manage and inform the environmental impact.
Information services can have a positive impact too, providing current and predicted air quality levels, as well as services encouraging people to make more sustainable changes in their regular travel choices, like the Active Travel Logger project IBI has been working on for the NTA in Ireland. Making clean public transport a viable alternative can be supported through more readily understood route maps, clearer information at stops, prices and how to pay.
ITS is also an important element of Low Emissions Zones (LEZs) and Clean Air Zones. These are approaches cities are increasingly using to help mitigate the negative effects of traffic pollution. The first LEZ – a designated area where targeted action is taken to improve air quality – was introduced in Stockholm in 1996, with hundreds now in place around the world. In the UK and Ireland, IBI has worked on projects such as London Congestion Charging, Mersey Gateway and the M50, Dublin, providing us with real insight into the operational aspects of vehicle access monitoring and enforcement.
In terms of design we can look to a wide range of options including: building ventilation systems; orientation of building and roads to the prevailing wind; landscaping to encourage walking; the careful positioning of public transport stops and taxi ranks; and safe, efficient walking/cycling routes away from the roadside.
What’s the vision for the future?
We want urban areas to be enjoyable and healthier places, where people want to live, work and visit; balancing the needs of all. This requires a range of supporting and complementary measures at all levels – from the individual, to businesses, to local authorities and government initiatives and investment. The challenges and questions for all parties, whether road operators, consultants or solutions providers, appears to be three-fold, but in all cases, require us to examine air quality at a micro rather than macro level.