Originally Posted by MSUcommuter
Carbon dioxide (CO2) is formed when a hydrocarbon fully reacts with oxygen in combustion. Carbon monoxide (CO) is formed when hydrocarbons combust with an insufficient amount of oxygen.
both are found in car exhaust, both are greenhouse gases. however, exhaust from automobiles is hardly the cause of the problem with this global increase of the gases. If every person in the US drove a hummer, the total amount of CO and CO2 emissions for a year would hardly amount to the levels given off in a single volcanic eruption. I'm not sure offhand how many hundreds/thousands of volcanoes go off in a year, but there's a lot. The problem is with the big industries and chemical plants and whatever else just pouring smoke out. Yet our president refused to sign the Kyoto Protocol, saying it would cost our big american companies too much money to help the environment.
Volcanoes do give off a fair amount of CO2, but there's also a natural reduction, a "re-fossilisation", of CO2 through sedimentation of calcium carbonate from various marine life forms as well as through other processes. That balances much of the natural addition of fossil CO2.
Motorised traffic typically represents 20-30% of the total fossil CO2 emissions of a country.