Multiple benefits from stricter global vehicle emission controls

Non-CO2 air pollutants from motor vehicles have traditionally been controlled to protect air quality and health, but they also affect climate. In a new study, a global composition-climate model was used to examine the integrated impacts of adopting stringent EU air pollutant emission standards for road vehicles in 2015 in many developing countries.

Relative to a baseline scenario which assumed no extra controls on top of currently proposed or adopted standards, implementation of the tighter EU emissions and fuel standards as from 2015 would lead to annual benefits in 2030 and beyond of:

  • 120,000–280,000 avoided premature air pollution-related deaths;
  • 6.1–19.7 million metric tons of avoided ozone-related yield losses of major food crops;
  • $US 0.6–2.4 trillion avoided health damage; and,
  • $US 1.1–4.3 billion avoided agricultural damage.

Moreover, the tighter standards resulted in mitigation of approximately 0.2°C of northern hemisphere extratropical warming during 2040–2070. Note that there is significant uncertainty regarding the estimated cooling effect, primarily relating to black carbon and due to the poorly quantified indirect effects on clouds and albedo of this pollutant. Including the uncertainty range would show a cooling of between 0.03 and 0.34°C.

Tighter vehicle emission and fuel standards are thus extremely likely to mitigate short-term climate change in most cases, in addition to providing large improvements in human health and food security. These standards will not reduce CO2 emissions, however, which are required to mitigate long-term climate change.

Source: Climate, health, agricultural and economic impacts of tighter vehicle-emission standards. By D. Shindell, M. Walsh, et al. Published in Nature Climate Change, Vol 1, April 2011.

In this issue