Consider these two statements:
- Ships are the most energy efficient way to transport goods. They also have the smallest carbon footprint per ton of any means of transport.
- Ships are major polluters. One large container ship emits as much sulfur-oxide as fifty million cars.
Which statement is true? They both are. Ships are incredibly energy efficient and most large ocean going ships burn very dirty fuel. The comparison between the container ship and the cars is more than a bit unfair as the most gasoline around the world now has a very low sulfur content. In terms of other pollutants ships are cleaner than cars or trucks. Ships emit far lower CO2 per ton carried than either truck or automobiles, for example. Nevertheless, residual fuel, often referred to as Bunker C, is very dirty and highly polluting.
Recently the Environmental Protection Agency( EPA) and the US ports of New York and Los Angeles have taken steps to limit the scope and impact of that pollution. Landmark EPA regulations to reduce air pollution from ships off the East and West coasts of North America went into effect on August 1st. Ships operating in US coastal waters will now be required to burn a lower sulfur fuel. Environmental groups are pleased, while some in the cruise industry are not. As reported by Scientific American: