Macroeconomic impacts of proposed climate change mitigation strategies for transportation in Southern California

We evaluate the potential regional macroeconomic impacts of a set of eighteen greenhouse gas (GHG) mitigation policy options intended to enable the Southern California Association of Governments (SCAG) to comply with the California's emission reduction targets related to transportation and land use. The Regional Economic Models, Inc. (REMI) Policy Insight Plus (PI+) and TranSight (TS) Models were applied in the analysis by carefully linking technical and microeconomic aspects of each mitigation option to the workings of the regional economy. We account for key considerations, such as the extent to which investment in mitigation options would be generated from new revenue sources or would displace ordinary private business investment. Our results indicate that the combined eighteen policies could generate an employment gain of almost 14 thousand jobs per year and result in an increase in GDP of $22 billion over the entire planning period from now to 2035. Sensitivity analyses of key assumptions and parameters for the transportation and land use policies indicate that the results are robust.