AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Air Quality and Health Co-benefits of Different Deep Decarbonization Pathways in California
BIN ZHAO, Tianyang Wang, Zhe Jiang, Yu Gu, Kuo-Nan Liou, Yifang Zhu, University of California Los Angeles
Abstract Number: 855 Working Group: Urban Aerosols
Abstract As the world’s fifth-largest economy, California has committed to reduce its greenhouse gas (GHG) emissions by 80% below 1990 levels by 2050. The 2015 Paris Agreement further necessitates the target of net-zero GHG emissions. While previous studies have shown that GHG reductions could synergistically decrease air pollutant emissions, limited research has been conducted to compare the air quality and health co-benefits of different technology pathways towards deep decarbonization. Using an integrated approach that combines energy and emission technology modeling, high-resolution chemical transport simulation, and health impact assessment, we find that achievement of the 80% GHG reduction target would bring substantial air quality and health co-benefits. The co-benefits, however, highly depend on selected technology pathway largely because of California’s relatively clean energy structure. Compared with the business-as-usual levels, a decarbonization pathway that focuses on electrification and clean renewable energy is estimated to reduce concentrations of fine particulate matter (PM2.5) by 18-37% in major metropolitan areas of California and subsequently avoid about 12,100 (9,600-14,600) premature deaths. In contrast, only a quarter of such health co-benefits, i.e., 2,800 (2,300-3,400) avoided deaths, can be achieved through a pathway focusing more on combustible renewable fuels. After subtracting the cost, the net monetized benefit of the electrification-focused pathway still exceeds that of the renewable fuel-focused pathway, indicating that a cleaner but more expensive decarbonization pathway may be more preferable in California. Achieving net-zero GHG emissions beyond the 80% reduction target requires bioenergy with carbon capture and sequestration (BECCS) technology to offset some GHG emissions. BECCS technology, whereas supporting the net-zero target, would emit considerable air pollutants and increase about 400 premature deaths, suggesting a potential trade-off between climate benefits and health co-benefits of ambitious climate policies.