Air pollution is the leading global environmental health risk factor according to the World Health Organization. Implementing policies that reduce greenhouse gas emissions can also reduce the outdoor levels of air pollutants that harm human health by targeting the same emission sources. Dr. Rebecca Saari, an Assistant Professor at the University of Waterloo, presented the relationship between climate policies and health co-benefits at the SOCAAR seminar held on March 2, 2016.
The air quality co-benefits of climate policies can be estimated using an integrated modeling framework developed by Dr. Saari and colleagues. The framework combines advanced models of the United States’ economy and atmosphere to compare air quality co-benefits to policy costs across different regions and income groups. The main issues that were addressed in the talk were: i) When do air quality co-benefits matter and who gets them? ii) Can air quality co-benefits “pay for” climate change and clean energy policies?
Using the model to assess trading carbon dioxide emissions within the United States, it was found that cost-effective policies have co-benefits that exceed costs. When emission trading occurs between different States, the policy is more cost-effective with little effect to air quality co-benefit. This is because particulate matter gets shifted around rather than actually get reduced. But the ozone reductions are twice as valuable for the lowest income households as for the highest income households. The inequality in exposure makes ozone reductions more valuable for low income households. The analysis show that most cost-effective policies have air quality co-benefits that can completely offset their costs.