Furthermore, this would also deliver a net annual reduction of at least 200 MtCO₂e from short-lived climate pollutants in 2030 (using GWP-100 values). Climate benefits in the near-term (estimated using a GWP-20) are more than three times as large given the rapid benefits that the control of black carbon provides. For countries that are still far from reaching the Euro 6/VI equivalent standard, an interim policy target of Euro 4/IV-equivalent standards and 50 ppm sulfur fuel is a reasonable goal that provides substantial benefits, the authors suggest.

This report quantifies a subset of the global health impacts of motorized on-road vehicles in urban areas, focusing on direct emissions of the most damaging pollutant: particulate matter with a diameter of 2.5 micrometers or less (PM_2.5). The analysis quantifies how emissions are changing under currently adopted vehicle and fuel regulations and to what extent emissions and health problems would decline in the event of progressive improve- ment in fuel and vehicle standards. Because this analysis is only able to capture a subset of the full health effects attributable to the global transportation fleet, the estimated benefits of stringent fuel and vehicle standards are likely to be conservative.

—Chambliss et al.

The report compares the progress made under currently adopted policies (Baseline Policy scenario) against a scenario including global adoption of world-class vehicle emission and fuel quality requirements (Accelerated Policy scenario) through 2030.

• The Baseline Policy scenario assumes no new policies on vehicle emissions and fuel quality beyond those currently implemented or adopted.

• The Accelerated Policy scenario assumes all regions progress toward Euro 6/VI–equivalent new vehicle emission limits and fuel quality by 2030. Since Africa and the Middle East today have significantly higher sulfur levels and few regulatory standards in place compared with the rest of the world, this scenario assumes that these regions will achieve an interim target of 50 parts per million (ppm) sulfur fuel and Euro 4/IV–equivalent standards by 2025. All other regions are slated to achieve 10 ppm sulfur fuel and Euro 6/VI–equivalent standards by 2025 or earlier.

  In regions that have already adopted advanced standards for on-road vehicles, such as the EU-28, the United States, Canada, Japan, Australia, and South Korea, next-generation standards are adopted in 2025. Next-generation standards would target new reductions in emissions of NO_x and non-methane hydrocarbons (HC), which are precursors to ozone and secondary particulate matter.

Baseline and Accelerated Policy timeline for light-duty vehicles. Chambliss et al. Click to enlarge.

Exposure to vehicle emissions is estimated from a model that converts tank-to-wheel emissions of PM_2.5 to urban concentrations with the aid of a global intake fraction database.

The report makes three advances over previous studies, the authors noted.

1. The analysis uses a global emissions model with comprehensive, validated, and current global activity and regulatory data.

2. The report utilizes a new global-to-local-scale emissions to health impacts framework designed for rapid policy analysis.

3. It puts forward a new policy roadmap that recognizes the timing needed to meet the legislative and technical requirements of new fuel or vehicle emission standards.

Highlights of the analysis include:

• 50% of urban vehicle emissions and associated health impacts currently occur in regions that account for only 20% of global vehicle activity, especially developing regions of the Middle East, Africa, Latin America, and the Asia-Pacific.

• Diesel trucks and buses, especially those with minimal emission controls, account for more than 80% of global fine particle and nitrogen oxide emissions from road vehicles.

• Accelerated adoption of stringent fuel and vehicle standards in those jurisdictions that do not currently mandate the equivalent of Euro 6/VI or U.S. Tier 3 regulations, would prevent 210,000 premature deaths in 2030 and mitigate 1.4 GtCO₂e (applying GWP-100 metric) cumulatively from 2015 to 2030, 95% of which would come from reductions in black carbon. The climate benefits are 3.5 times greater when considering near-term impacts (using GWP-20).

• China and India will bear the two largest single-country health risks, accounting for 65% of the global increase in early deaths by 2030 without further policy action. Accelerated policy adoption in China and India would prevent 90,000 early deaths in the year 2030, about 40% of the global total.

Optimized policy roadmaps for reducing particulates and associated early deaths vary from region to region, but they all rely on two strategies that should be implemented concurrently: tighter vehicle emission standards and more stringent fuel quality standards. In all regions, progressing to Euro 6/VI–equivalent standards for new and imported vehicles as expeditiously as possible is of paramount importance, either in a single leap or through intermediate standards. Governments should coordinate the implementation of vehicle emission standards with a national pathway to ultra-low-sulfur fuel, which is not only required for the most advanced emission controls but can also reduce emissions from the legacy vehicle fleet.

—Chambliss et al.

Resources

• Sarah Chambliss, Josh Miller, Cristiano Façanha, Ray Minjares, Kate Blumberg (2013) “The Impact Of Stringent Fuel And Vehicle Standards On Premature Mortality And Emissions”