If all the cars on the planet were completely eliminated, less than 20 percent of greenhouse gas emissions would be affected, and far less of other pollutants.
There are about 90,000 huge container ships worldwide that typically run on high sulfur bunker fuel oil.
New research indicates that each of the biggest ships emit as much as 50 million cars.
That means the 15 largest ships may be emitting more than all the world’s cars.