Climate Change Mitigating Health Co-Benefits of Healthy Transportation

Background:

Assessments of transportation alternatives, such as bicycling, walking, and public transit, can better guide infrastructure investments with health benefits in mind. While much has been documented on health outcomes associated with transportation systems, quantification of specific health risks and benefits of alternative transportation is lacking. In addition to reducing greenhouse gas emissions and air pollutants, decreasing the number of vehicle miles traveled by promoting bicycling and walking provides physical activity, an important component in preventing obesity and other chronic diseases. Bicycling, walking and other forms of active transport, therefore, could play a critical role in promoting public health.

Methods:

In this pilot study, we apply the Integrated Transport and Health Impact Model (ITHIM) at census tract level across the United States. We estimate the health benefits resulting from alternative land use scenarios through their effect on transportation mode choice and infrastructure.  In order to quantify and reduce uncertainty in each step of the process, we combine large observational datasets from partner communities, bikesharing services, and geolocated travel and fitness databases with high-resolution emissions/chemical transport modeling.  We assess net gains in health and reductions in greenhouse gas emissions and fine particulate matter through different scenarios for each Metropolitan Statistical Area (MSA).

Findings:

Results of this assessment define the sensitivity of health estimates to different air quality modeling methods and scales of analysis. Our findings describe how health co-benefits can be assessed at scales as fine as the US Census Tract, which is equivalent to individual neighborhoods in many large cities.

Conclusions:

This work benefits the environment, public health, and transportation planning by quantifying the health co-benefits of active transportation scenarios across the United States. Quantifying the health impacts of transportation systems can lead to better information and increased financial support on which to base healthy transportation planning.