Monday, October 25, 2010
Arctic warming and increased shipping
The increased Arctic ship traffic will not only mean more greenhouse gases in the atmosphere but will also bring with it air pollution in form of engine exhaust particles which could increase warming in this part of the world by some 17-78 percent.
James J. Corbett, professor of marine science and policy at UD said that "One of the most potent 'short-lived climate forcers' in diesel emissions is black carbon, or soot, and ships operating in or near the Arctic use advanced diesel engines that release black carbon into one of the most sensitive regions for climate change."
These tiny air pollutants are produced by ships as the result of incomplete burning of marine fuel. Once released, these particles act like heaters because they absorb sunlight, both directly from the sun, and reflected from the surface of snow and ice.
In order to give more clearer image on the potential impact of black carbon and other ship pollutants on climate the scientists produced high-resolution (5-kilometer-by-5-kilometer) scenarios that not only account for growth in shipping in the region through 2050, but also outline potential new Arctic shipping routes.
The scientists found that:
* Global warming potential in 2030 in the high-growth scenario suggests that short-lived forcing of around 4.5 gigatons of black carbon from Arctic shipping may increase the global warming potential due to ships' carbon dioxide emissions (around 42,000 gigagrams) by some 17-78 percent.
* Ship traffic diverting from current routes to new routes through the Arctic is projected to reach 2 percent of global traffic by 2030 and 5 percent in 2050.
* A Northwest Passage and Northeast Passage through the Arctic Ocean would provide a distance savings of about 25 percent and 50 percent, respectively, with coincident time and fuel savings. However, the scientists said that tradeoffs from the short-lived climate forcing impacts must be studied.
* With controls, the amount of Arctic black carbon from shipping can be reduced in the near term and held nearly constant through 2050.