Air Quality Co-Benefits in Climate Policy


This research project investigates the air quality co-benefits of climate policy. Reduced burning of fossil fuels curbs not only CO2 emissions but also emissions of hazardous co-pollutants, such as particulate matter. The extent of air quality co-benefits relative to CO2 reduction varies across regions and pollution sources, and hence the distribution of emissions reductions matters for both efficiency and equity.

This research project investigates spatial and source-wise variations in the magnitude and distribution of air quality co-benefits of climate policy. The project has three components:

(1) Air quality co-benefits in California: We examine the air quality benefits of emissions reductions mandated by the state’s Global Warming Solutions Act. One issue of particular interest is whether exposure to co-pollutants from mobile sources is correlated with industrial point source exposure, further multiplying the cumulative impacts arising from exposure to multiple point sources.

(2) Air quality co-benefits in Europe: We use data on industrial point source emissions from the European Pollutant Release and Transfer Register to investigate intersectoral and regional variations in co-benefits. Such analysis will be especially important as the EU moves forward with its Emissions Trading Scheme (EU-ETS) to reduce greenhouse gas emissions. If the air quality co-benefits of emissions reductions vary substantially, a case can be made for policies that seek greater reductions in sectors and/or regions where the co-benefits are largest.

(3) Valuation of air quality co-benefits and their distribution: Connecting our analysis of the distribution of co-pollutant impacts to prior studies that have estimated the aggregate monetary value of the air quality co-benefits of climate policy, we examine how the monetized costs are distributed across pollution sources, geographic regions and population subgroups, how recognition of these costs affects measures of economic inequality, and whether racial or ethnic dimensions of the cost burden after controlling for income raise additional concerns and legal bases for addressing air quality issues in climate policy.