ARB Research Seminar

This page updated June 19, 2013

Part I: Geospatial Intermodal Freight Transport Model with Cargo Analysis and Part II: Improved Geospatial Scenarios for Commercial Marine Vessels

James J. Corbett, P.E., Ph.D., College of Earth Ocean and Environment, University of Delaware

July 07, 2011
Cal EPA Headquarters, 1001 "I" Street, Sacramento, CA

Presentation: 1. 2.
Research Project



In this part of the seminar, results of a study that further developed the Geospatial Intermodal Freight Transportation (GIFT) model, configured the model with California-specific data, and applied the configured model in a case study of the possible benefit of shifting freight transportation from trucks to rail. Employing a Geographic Information System (GIS)-based model that integrates three transportation network models (road, rail, water), joined by intermodal transfer facilities (ports, railyards, truck terminals) in a single GIS "intermodal network" modified to capture energy and environmental attributes, a Case Study was performed to explore the difference in emissions under Least-travel-time versus least-CO₂ routing of goods movements. The Case Study estimates CO₂ emissions to be approximately 2.89 million metric tons (MMT) of CO₂ attributable to the container traffic of the three major West Coast ports (LA-Long Beach, Oakland, and Seattle) using a least-time scenario (which comprises mostly trucks). Our estimation of a total reduction of approximately 1.7 MMT of CO₂ occurs through a nationwide modal shift of West Coast port-generated goods movement; within California state air basins, this reduction is near 0.5 MMT CO₂. Overall, this research demonstrates how the GIFT model, configured with California-specific data, can be used to improve understanding and decision-making associated with freight transport at regional scales.


In this second part of the seminar, results of a study to update geographically resolved commercial marine emissions inventories and scenarios for cargo traffic in shipping lanes serving U.S. continental coastlines. A primary objective of this project is to update commercial marine emissions (CMV) inventories by providing geographically resolved vessel specific estimates of commercial marine vessel emissions in North American waters that are consistent with earlier studies for the California Air Resources Board (ARB). Vessel-specific growth trends describing trade and energy requirements for North American cargo and passenger vessels are applied to 2002 data to produce unconstrained business as usual (BAU) estimates for 2010 (prior to international sulfur regulations), and a 2020 scenario assuming International Maritime Organization (IMO)-compliant reductions in global fuel sulfur. Two growth scenarios are illustrated: Scenario 1, approximating the same composite growth rates as previous work (pre-recession); and Scenario 2, employing lower growth rates. The advantages of vessel-type specific growth patterns are discussed, with some examples of how the work supported the North American ECA development. Implications of this work for evaluating potential additional air pollution and climate impacts from shipping, along with health effects, economic policy instruments, and mitigation policies will be discussed.

Speaker Biography

James J. Corbett, PE., Ph.D., is a Professor in the College of Earth Ocean and Environment with joint appointment in Civil and Environmental Engineering in the College of Engineering at the University of Delaware. Professor Corbett conducts technology-policy research related to transportation, including groundbreaking research on air emissions from maritime transport, energy and environmental impacts of freight transportation, and assessment of technological and policy strategies for improving goods movement. Dr. Corbett is a leading collaborator in a multi-university Sustainable Intermodal Freight Transportation Research (SIFTR) program, an international research collaboration to improve the effective use of highway, waterway, railroad, and air transportation infrastructure. Co-directed by team partners at the University of Delaware and the Rochester Institute of Technology, and extending more than a decade of sustainability research in large freight systems, SIFTR is working with colleagues and partners across the nation to identify achievable targets for sustainable goods movement. Among more than 175 publications related to shipping and multimodal transportation, Dr. Corbett coauthored the 2000 IMO Study on Greenhouse Gases from Ships, the Second IMO Greenhouse Gas Study 2009, and wrote the Marine Transportation and Energy Use chapter in the 2004 Encyclopedia of Energy. He contributed to the Environmental chapter of the Arctic Marine Shipping Assessment (2009), and led development of scenarios to quantify environmental impacts of future Arctic Shipping.

For a complete listing of the ARB Research Seminars and the related documentation
for the seminars please view the Main Seminars web page