CO2 Restrictions and Cargo Throughput Limitations at California Ports: A Closer Look at AB 32 and Port-to-Port Shipping

Abstract

Port operations generate economic benefits as well as environmental impacts. As climate change gains greater focus, ports must address emissions reduction challenges without sacrificing productivity. In this article, linear modeling of CO2 emissions from ocean-going vessels is used to see if the California Greenhouse Gas Solutions Act (Assembly Bill 32) restricts cargo growth by setting targets for emissions reductions. By relating future emissions to cargo growth, this model predicts future CO2 emissions from ocean-going vessels for a 4.6% annual increase in cargo and a no-growth scenario. Findings show that even with three emissions reduction measures the target of Assembly Bill 32 cannot be reached without diverting cargo, providing evidence of a direct environmental constraint on port expansion. Using the results of this analysis, options to reduce emissions from ocean-going vessels with less cargo diversions are discussed, including implementation of new technologies and a cap-and-trade system.