The article lacks a description of which specific form of pollution is compared. When talking about pollutants is important to keeps the following points in mi

The article lacks a description of which specific form of pollution is compared. When talking about pollutants is important to keeps the following points in mind: - Is the pollutant effecting health? - Is the pollutant effecting climate change? - Is the amount of pollution locally concentrated or very distributed? Cargo ships typically have a very high emission of nitrogen Oxides (NOx) and sulphur dioxide. When emitted by cars / factories on the mainland these often strongly contribute to harmful smog especially in megacities or cities with poor ventilation. Also they can be generally bad to the ecosystem also on the water due to causing acid rain etc. The main pollutants on cargo ships have a very strong short term effect but are often out of the air in a few weeks. Because of that they don't rise to the atmosphere and don't directly contribute to long term climate changes. Thus I think the comparison in the article is very dangerous. When considering pollutants that effect climate change cars are more dominant. So depending on which effects are discussed reducing pollutions from cars can still be benefitial. As an additional thought, the polutions of the cargo ships are spread out over a very large geographich area while the exhausts of cars are much more concentrated around cities. So when considering ones own quality of living, cars have a much bigger impact. I think an article that better manages to discuss the subject is this one from the guardian: http://www.theguardian.com/environment/2009/apr/09/shipping-pollution http://www.theguardian.com/environment/2009/apr/09/shipping-... Excerpts: - Shipping is responsible for 18-30% of all the world's nitrogen oxide (NOx) pollution and 9% of the global sulphur oxide (SOx) pollution. - Shipping is responsible for 3.5% to 4% of all climate change emissions