28 October 2010
A new study coauthored by CIRES scientist at CSD Dan Lack takes a detailed look at what might happen if declining sea ice coverage due to climate change opens up new shipping routes in the Arctic, bringing air pollution to one of the world's last pristine environments.
"Currently there are very few local sources of pollution in the Arctic," said Dan. "Increases in ship traffic will create a significant local source of climatically significant pollutants."
Foremost among them is black carbon, or soot, emitted from the diesel ship engines. The new paper, published in the scientific journal Atmospheric Chemistry and Physics, presents a fine-scale inventory of emissions of important greenhouse gases, black carbon, and other pollutants under existing conditions and under different scenarios for the possible growth of shipping in the region.
The bottom line: more ship traffic has the potential to accelerate the climate change associated with shipping emissions.
Black carbon warms climate by absorbing heat directly from the sun as well as heat reflected by snow and ice. Ships emit black carbon because of the incomplete burning of marine diesel fuel. The new study finds that the emitted black carbon adds to the warming from the CO2 emissions of the ships, by as much as 17% to 78% in the high-growth scenario for future shipping in the Arctic region.
The paper also looks at how actions to reduce the soot emissions of the ships could mitigate the climate impacts. Control technologies to scrub pollutants emitted during the burning of the diesel fuel could keep black carbon nearly in check through 2050.
J.J. Corbett (University of Delaware), D.A. Lack (CIRES and ESRL CSD), J.J. Winebrake (Rochester Institute of Technology), S. Harder (Transport Canada), J.S. Silberman (GIS Consulting), and M. Gold (Canadian Coast Guard), Arctic shipping emissions inventories and future scenarios, Atmospheric Chemistry and Physics, doi:10.5194/acp-10-9689-2010, 2010.