WHO report urges greater attention to improved land use, rapid transit, cycling and walking to achieve health co-benefits from transport GHG emissions mitigation
|Urban density is one of the most important determinants of car use and transport-related energy consumption in cities. Source: WHO report. Click to enlarge.
Among strategies to reduce CO2 emissions in the transport sector, a shift to active transport (walking and cycling) and rapid transit/public transport combined with improved land use can yield much greater immediate health “co-benefits” than improving fuel and vehicle efficiencies, according to a new WHO (World Health Organization) report.
These strategies need more systematic study by the Intergovernmental Panel on Climate Change (IPCC)i in the assessment of transport mitigation measures, according to the report, Health co-benefits of climate change mitigation - Transport sector, released this week during the United Nations Framework on Climate Change Conference of the Parties (COP-17) in Durban, South Africa.
The report reviewed more than 300 studies on health outcomes from different types of land transport systems in a “scoping exercise” designed to identify those mitigation measures most closely associated with specific health co-benefits or risks.
The review is the latest product of WHO’s Health in the Green Economy initiative, which is considering available evidence on health impacts from climate mitigation strategies for key economic sectors, as reviewed by the UN’s Intergovernmental Panel on Climate Change.
The IPCC’s global assessment of mitigation options for the transport sector places the greatest emphasis on the mitigation potential of improving carbon efficiencies for private vehicles and fuels. In contrast, the WHO review found a stronger, and more positive, association with health benefits from rapid transit and dedicated walking/cycling systems—measures which are covered by IPCC, but not as systematically and with little note of health issues.
We have looked at the IPCC assessment through the lens of public health and come up with quite a different reading. Public/rapid transport and safe cycling and walking are the prototype of a transport system that is good for health; it so happens that these are good for climate too.—Dr. Carlos Dora of WHO’s Department of Public Health and Environment
Among the other key messages of the report:
Potential health gains of a shift from private motorized transport to walking, cycling and rapid transit/public transport include reduced cardiovascular and respiratory disease from air pollution, less traffic injury and less noise-related stress. In addition, large benefits are expected from increased physical activity, which can prevent some cancers, type 2 diabetes, heart disease and other obesity-related risks. Improved mobility for women, children, elderly and the poor, who have less access to private vehicles, enhances health equity.
Shifting from gasoline to diesel vehicles could increase emissions of health-damaging small particulates (PM10, PM2.5). IPCC’s assessment finds diesel vehicles have potential to reduce transport’s CO2 emissions. However, diesel engines typically emit higher concentrations of small particulates. In Europe, large shifts to diesel vehicles over the last decade are regarded as a cause of stable (but not lower) urban PM10 levels—despite the introduction of cleaner diesel technologies.
Transport-related health risks now cause the deaths of millions of people annually. For example, WHO estimates that urban air pollution (much of it transport-generated) kills some 1.3 million people annually. Additionally, traffic injuries kill another 1.3 million people every year, mostly in low- and middle-income countries. Some 3.2 million deaths annually are due to physical inactivity.
Overarching goals of healthy transport include: (a) reduced deaths and disease generally from transport-generated air, noise, and water pollution; (b) reduced exposures of disadvantaged groups to excessive transport-related injuries and health risks; (c) safer and more efficient access, especially for vulnerable groups, to jobs, schools, services and social opportunities; (d) increased physical activity, including through safe walking and bicycling; (e) reduced climate change emissions from transport that contribute to future, as well as present-day, health impacts.—Health co-benefits of climate change mitigation—Transport sector
These goals can be achieved via four main strategies, according to the report:
Compact land-use systems that increase density and diversity of uses.
Investments in, and prioritization of, transport networks for pedestrians and cyclists.
Investments in, and prioritization of, transport networks for rapid transit/public transport.
Transport engineering and traffic-calming measures that protect vulnerable road users from motorized transport’s hazards.
The report highlighted a number of policy tools to support health-oriented strategies:
Health impact assessment that identifies and addresses health co-benefits and risks at the planning stage, as well as measures to improve health and reduce health inequities.
Strengthened land-use/transport planning, codes and enforcement; for example, ensuring universal access to safe cycling and pedestrian routes and to rapid transit/public transport for basic routines.
Development and monitoring of healthy transport performance criteria and indicators, including better indicators for active travel/physical activity; use of non-motorized modes and public transport; air/noise pollution exposures; pedestrian injuries; and mobility/access.
Economic evaluation and assessment methods that fully account for the health co-benefits of walking, cycling and rapid transit/public transport use.