LEDS in Practice: Breathe clean by reducing greenhouse gas emissions from urban transport

Published: 5th July 2016 16:30Last Updated: 13th July 2016 14:07
leds in practice breath clean air quality 1 0 - climate adaptation.

 Photo by Simone D. McCourtie/World Bank


Low Emissions Development Strategies (LEDS) are central to the efforts of developed and developing countries to mitigate current and future greenhouse gas emissions, which if unchecked will accelerate climatic change and further exacerbate existing vulnerabilities, and thereby undermine efforts to adapt to climate change.

As a result of various push-pull factors, including impacts relating to climate change, migration from rural to urban settings (urbanisation) is increasing. This is increasingly exerting pressure on the capacity of cities, requiring interventions in order to maintain the health and security of their growing populations. In parallel to this, economic growth in developing and developed countries alike is resulting in an increased need for, and dependence on, public and private transport. This presents both a challenge and opportunity for cities to mitigate increasing air pollution and carbon emissions. In response to this the Transport Working Group at Low Emission Development Strategies Global Partnership (LEDS GP) has released a series of papers exploring the many benefits of low carbon urban transport (see links under further resources), of which this is one.

Breathe clean

As well as accounting for 23% of the world’s energy related greenhouse gas emissions, fossil fuel consumption by motorized transport releases exhaust fumes that contain particulate matter (PM) including black carbon, which is hazardous to human health and a contributor to climate change. High atmospheric concentrations of tropospheric ozone and black carbon increase the risk of many respiratory and cardiac diseases—placing an immense burden on healthcare systems. The United Nations Environment Programme (UNEP) estimates that each year 2.4 million premature deaths from outdoor air pollution could be avoided, and by 2050 global warming could be reduced by up to 0.5°C if short lived climate pollutants are mitigated promptly.

The health impacts of air pollution also contribute to individual and community vulnerability and broader inequality since ill-health impedes the ability of individuals to make a living, and may increase their dependence on family and community members.

Shifting to low carbon transport plays a crucial role in the fight against air pollution as transport accounts for 27% and 22% of total global PM2.5 and PM10 emissions, respectively. Low carbon transport solutions would achieve three interlinked benefits:

  • improve health and reduce premature deaths
  • avoid the resulting loss of economic productivity and related healthcare costs
  • slow the rate of near term climate change. Epidemiological and toxicological studies find strong evidence that vehicle emissions are related to clinically significant health ailments.

This paper* presents two case studies from cities that have taken action on air quality to improve public health and have realized the benefits of reduced emissions with the implementation of low carbon transport policies. The paper describes the use of congestion pricing in Stockholm, Sweden and local air pollution management in Kathmandu Valley, Nepal to reduce air pollution, and provides details of the design, implementation and the results of these projects to date.

*download from the right-hand column or via the link under further resources.

Key Messages

  • Air pollution not only diminishes the quality of life in cities around the world, but also threatens the prosperity of urban economies since ill-health reduces productivity.
  • Health issues arising from air pollution impedes the ability of individuals to work and earn a living, thereby increasing their vulnerability to external stressors such as climate change.
  • Particularly hazardous for health are emissions of black carbon, a component of particulate matter, which is a known cause of respiratory and carcinogenic diseases and a significant contributor to global climate change.
  • The clear links between greenhouse gas emissions and particulate matter make low carbon transport an increasingly sustainable investment at local level—both by reducing emission levels and thus mitigating climate change; and by improving public health through better air quality.
  • For example:
    •  Congestion pricing in Stockholm, Sweden saves 14–18% of carbon dioxide equivalent emissions, cuts particulate matter by 9% and mono-nitrogen oxides by 7%—and generates revenue.
    •  Policy proposals in the Kathmandu Valley to reduce particulate matter are aiming to reduce bronchitis cases and asthma attacks, bringing massive economic savings of US$21 million for the nation, along with a major improvement in quality of life.

Further resources