With the shipping world set to address greenhouse gas emissions such as carbon dioxide at IMO’s fast-approaching July MEPC 59 meeting, now is an opportune time for the sector to consider other climate-forcing emissions such as black carbon, the light-absorbing element of soot that constitutes an increasing threat to the Arctic.  

Suspended black carbon particles not only heat the atmosphere by absorbing sunlight, but they also reduce the reflectivity of ice and snow, thereby increasing melting rates.  As lighter colored snow and ice recede and are replaced by darker, more light-absorbing matter such as water and land, warming is accelerated in a dangerous feedback mechanism.  A recent study finds that black carbon is responsible for a large share of Arctic warming; shipping contributes 3.6 and 1.7 percent of black carbon emissions in the United States and the world, respectively.

Commercial Arctic shipping is also fast becoming a reality.  The Arctic continues to warm at twice the rate of the rest of the world, and the region’s sea ice extent and thickness have decreased dramatically, allowing the fabled Northwest Passage and Northern Sea Routes to open in the summer of 2008.  Trans-Arctic shipping along these passages presents an attractive option for shippers that could save 9,000 kilometers, and substantial fuel costs, on voyages between Asia and Europe.  Further, oil and gas transport and cruise ship travel, which exploded from 50 ships in 2004 to 250 ships in 2007, will assuredly continue to grow in the Arctic.  

Many scientific experts assert that near-term black carbon mitigation efforts can limit warming and forestall cataclysmic “tipping point” events, such as the loss of the Greenland ice sheet and associated sea level rises.

While MARPOL Annex VI regulations for ECAs do not address direct particulate matter emissions and thereby black carbon, the IMO could take timely steps to create relevant standards and in the interim develop voluntary guidelines to reduce black carbon emissions from ships traveling in vulnerable Arctic waters.  Fortunately, there are available ways to decrease black carbon emissions that are cost-effective and practicable, through in-engine techniques (e.g: slide valves) and operations (e.g: “slow steaming”).  

The time to act on this issue is now.  Arctic shipping is beginning to ramp up and potential remedying measures may take several years to implement.  The IMO has the opportunity to exhibit leadership on the issue of climate change and should work to curtail all forms of climate-forcing emissions from ships.