Impacts of Panama Canal Expansion on U.S. Greenhouse Gas Emissions

International shipping is a significant contributor to global climate change, accounting for approximately 3.3% of global carbon dioxide (CO₂) emissions across all sectors. The expansion of the Panama Canal, scheduled to open in 2014, will improve available all-water routes for trade between the eastern United States and Asia, creating opportunities for both lower emissions and lower costs. The authors used data from the import and export projections of the FHWA Freight Analysis Framework 3 database to estimate the canal's impact on shipping emissions with and without the expansion project. The expansion is expected to reduce annual CO₂ emissions of U.S. East Coast–Asia trade by 1.4 billion kg in 2025, a per ton reduction of 2.69%. Along with design and operational improvements, the efficiencies created by increased opportunities for use of all-water routes and large vessels are expected to have a small but beneficial impact on greenhouse gas reduction efforts in international shipping.