text: In the world today, a major problem that still exsists is greenhouse gases. Cars emit a lot of gas that isn't good for the enviroment. In the first source, it says that people living in cities "is a huge impediment to current efforts to drastically reduce greenhouse gas emissions from tailpipes... passanger cars are responsible for 12 percent...in Europe...and up to 50 percent... in the United States."(paragraph 5) Exports mean to say that it is better for people to live in cities so they don't have to drive everywhere. This means that the more people that live in cities, the less gas goes into the air. In Paris, the city issued a ban for driving to try and reduce the smog. The second source says that "congestion was down to 60 percent in the capital of France, after five-days of intensifying smog." (paragraph 14) Only after five days of the no driving ban, more than half of the smog was gone in Paris. It also says that the amount of smog was almost as polluted at the city of Beijing, China, which is the most polluted city in the world. Bogota also did the same thing. They have an event called "A Day Without Cars." Participant Carlos Arturo Plaza says it is a good way "to take away stress and lower air pollution."(paragraph 24) They also got other cities, and even other countries, to follow suit and join the event. America faces the same problem as Paris; too many greenhouse gases are being put into the atmosphere. President Obama has a goal that he wasnts to achieve and  that is to try and make the enviroment healthy. The last article says that driving less "will have beneficial implications for carbon emissions and the enviroment, since transportation is the second largest source of America's emissions, just behind power plants."(paragraph 34) This implies that the amount of gases let into the air will be reduced. If peolpe didn't drive as much from place to place, the world would be a happier, healthier place.