For much of the early history of the car, no consideration was given to various environmental effects caused by the automobile.

American cars and trucks are a huge source of global warming pollution. U.S. autos emit more than 333 million tons of carbon dioxide each year, more than one-fifth of the nation's total carbon dioxide emissions.

Compared with the rest of the world, American auto emissions are disproportionately high. With only 5 percent of the world's population and 30 percent of the world's automobiles, the United States contributes 48 percent of the world's automotive CO2 emissions.

Any serious effort to fight global warming must include cutting auto emissions. Check out the areas below for the different ways cars impact our environment.