Operational and design changes in the aviation and marine transportation sectors could reduce global greenhouse gas emissions by more than 50 percent by 2050.
Currently, aviation and marine transportation account for approximately 5 percent of total domestic greenhouse gas emissions and 3 percent of global greenhouse gas emissions. The study “Greenhouse Gas Emissions from Aviation and Marine Transportation: Mitigation Potential and Policies” explores potential future solutions to reducing emissions from air and water transportation.
The report from the Pew Center on Global Climate Change was written by two UC Davis graduate students, David McCollum and Gregory Gould, and David Greene of the Oak Ridge National Laboratory.
Demand for aviation and marine transportation is increasing rapidly according to McCollum, a Ph.D. candidate in Transportation Technology and Policy. As developing countries industrialize, aviation and marine transportation increase. More people fly for business or personal travel and leisure. Marine transportation moves more freight as developing countries produce more goods. As populations continue to grow, aviation and marine transportation will continue to grow, McCollum said, who is also a graduate researcher in the Sustainable Transportation Energy Pathways (STEPS) program at UC Davis’ Institute of Transportation Studies.
In comparison to cars, trucks and buses, aviation and marine transportation have not received the attention they deserve regarding researching options for alternative fuels in the United States until recently, McCollum said.
Prospective aviation and marine transportation operational solutions include implementing improved air traffic control and ship routing systems that decrease the amount of wasted fuel being burned. Improving plane and ship engine efficiency by, for example, using lightweight materials to construct planes and ships could reduce fuel use. Alternative fuel options for aviation and marine transportation are more limited than resources for cars and trucks. Planes and ships could use biofuels to reduce greenhouse gas emissions.
Reducing demand for aviation and marine transportation is a difficult feat, McCollum said. High-speed rail could replace air travel, but it is limited to shorter distances, such as the distance from San Francisco to Los Angeles.
The report noted that demand reduction of marine transportation is quite challenging since ships efficiently transport large quantities of goods across vast areas at a low cost.
Regulating global aviation and marine transportation greenhouse gas emissions is difficult, said Gould, a Ph.D candidate and research assistant in the Department of Civil and Environmental Engineering at UC Davis. In travel between countries, it is unclear who is responsible for emissions. It is especially difficult to regulate marine transportation because the ocean is not owned by a specific country, said Gould, who is a member of the UC Davis Institute of Transportation Studies.
Domestically, establishing policies and rules to regulate aviation transportation’s greenhouse gas emissions is simpler, Gould said. For example, a specific organization like the Environmental Protection Agency can regulate United States air travel emissions.
Internationally, it is difficult to define responsibility of the emissions. The International Maritime Organization can establish emission limitation rules. Regulating shipping as a separate entity among all nations would be difficult because it requires a high level of cooperation between countries, Gould said.
UC Davis’ STEPS program tackles big sustainable energy issues. It focuses on four fuel tracks: hydrogen, biofuels, electricity and fossil fuels. The STEPS program is unique in that it receives input from a large body of researchers, including the government and large industries, said Peter Dempster, manager of STEPS.
THERESA MONGELLUZZO can be reached at firstname.lastname@example.org.