Panama Canal expansion: Emission changes from possible US west coast modal shift

Abstract

Background: We analyzed the potential for the Panama Canal expansion to change CO2 and criteria pollutant emissions (oxides of nitrogen, oxides of sulfur and particulate matter) from Asia-US container flows by estimating the modal shift from landside truck/rail network to larger ships enabled by canal expansion. We develop an intermodal case study comparison within the Geospatial Intermodal Freight Transportation framework, assuming potential diversion of 1.2 million 20-foot equivalent units (TEUs) to 5000 origin-destination pairs. Results: Potential TEU diversions of land-bridge transport through an expanded canal reduced mode-specific emissions substantially, but land-bridge emission reductions due to cargo diversion to post-Panamax vessels, with lower emissions per TEU, cannot offset higher waterborne emissions from longer routes. Conclusion: Green-freight policy measures must consider multimodal network solutions to maximize emission benefits. © 2012 Corbett et al.