The idea that automobile emissions contribute significantly to climate change is not a new idea in the world, Through burning fossil fuels, cars release carbon dioxide and other sources of pollution that worsen the air and contribute to the greenhouse gases in the atmosphere. An article discussing climate change from Greenpeace (http://www.greenpeace.org/international … s-answers/) states that 13% of total global greenhouse gas emissions come from transport, which includes driving, and estimate that the percentage could rise to 30-50% by 2050. Increased greenhouse gases in the atmosphere from anthropogenic activity results in an enhanced greenhouse effect, as an increasing amount of the Sun's heat remains trapped on Earth. In efforts to reduce the emissions from automobiles,  the federal Clean Air Act Amendments of 1990 requires emissions testing in large, urban areas which do not meet certain air quality standards. These tests ensure that motor vehicles are not releasing dangerous amounts of pollution that could severely adulterate  air quality. Recently, there was a scandal in the United States over Volkswagen emission testing (read more here: http://www.bbc.com/news/business-34324772). According to the Environmental Protection Agency (EPA), some Volkswagen vehicles being sold in America had devices in diesel engines that could recognize when the car was undergoing an emissions test and change the car's performance to improve the results. Once on the rode, these vehicles switched off from this test mode, and their engines emitted nitrogen oxide pollutants up to 40 times above what is allowed in the United States. Although Volkswagen was caught in the midst of their deception, this story makes me consider how cars effect air quality in general. Even with these emissions tests, all cars still contribute noxious pollutants such as carbon monoxide, nitrogen oxide and hydrocarbons that are nothing but detrimental to human health, which supports why people should find alternatives to driving as a method of transportation whenever possible. I know I will definitely try to use either public transportation, bike, or walk more often.