PNNL

Abstract

New developments in Integrated Assessment Models (IAMs) include enhanced technological detail, greater spatial and temporal resolution, and the addition of air pollutant emissions, many of which also impact radiative forcing. While IAMs historically have been applied at the global level to investigate greenhouse gas (GHG) emission trends and mitigation strategies, these developments raise the potential for some IAMs to be applied for an additional purpose: supporting national- and finer-scale, coordinated, long-term, environmental, air-quality, and energy planning. We present a version of the Global Change Assessment Model (GCAM) with U.S. state-level resolution (GCAM-USA) and representations of existing U.S. air quality regulations. GCAM-USA air pollutant emission outputs are compared to a base-year inventory and future projections that were previously used in U.S. Environmental Protection Agency (EPA) regulatory activities. GCAM-USA projections are also compared with those of the base GCAM model in which the U.S. is represented as a single region. A Quality Metric (QM) is applied in this comparison. The QM also is used to quantify GCAM-USA performance for each pollutant at the sectoral and state levels. This information provides insights into the types of applications for which GCAM-USA is currently well suited and highlights where additional refinement may be warranted.