Smog is proof that pollution is a problem. Cars produce pollution from the combustion of gasoline which causes extreme smog in dense cities. Paris is one of the cities that has smog mostly from cars. So most cities are now trying to convince people that live there to switch from cars to buses, walking, or riding a bicycle.

Paris has recently set a partial driving band in there city because of record pollution levels that were being caused by automobiles. The smog in paris had become so intense and severe that they had to create a driving band to correctly limit the pollution being made. "...Paris had 147 micrograms of particulate matter (PM) per cubic meter compared with 114 in Brussels and 79.7 in London."(Source 2,17). This extremly high smog ratio and prooves the pollutin from automobiles is causing the problem because after a week with the band the smog had almost cleared fully.

Colombia has the same problem as Paris. Instead of weekly baneds on even and odd licensed plated vechiles Colombia has a 100% no car day with only taxis and buses allowed into the city. This day is dedicated to help people find new ways of transportation instead of personal veichles. Any violaters of the law face a $25 dollar fine. This event is normally only in the capital of colombia and has been that way for 7 years, but this year two new cities joined in on the event (Cali and Valledupar). Because of this event 118 miles of bicycle paths and new and improved sidewalks have been constructed, so many people are able to switch from cars to bikes and walking. All of these efforts have decreased traffic and now new restraunts and shopping malls have been created. Plus there has been a signifigant decrease in smog.

America is also trying to get in on the anti-pollution ideas coming from Colombia and Paris. Since America's love for vechiles is starting to decrease they are now able to try and decrease the vehcile usage. Population growth is a high contributing factor in this because with this cities slowly become denser and denser allowing for people to be able to get to the places they need to be without a car. They can walk there along the many sidewalks in the city. In New York there is a program to share a bicycle which has increased the bridge and tunnel tolls for cars because of all the people who no longer use their cars making cars more expensive to drive. Their has also been a drop in the young adult getting their license because they simply do not need it."A study last year found that driving by young people decreased 23 percent between 2001 and 2009"(Source 4, 41). Which shows most people are slowly decreasing the amount of driving they do. Driving in America is not as nesscary as it was before and it shows.

Smog is a big problem in all cities like Colombia and Paris and they are almost all taking action to decrease it and its been working. Many cities and countries goal are to decrease the amount of their citizens require driving. This will in turn cause their citizens to resort to other means of transportation and slowly decrease pollution in alot of areas. This shows why and how you can help the cause in your city by switching to non-polluting ways of traveling and how cities really do need your help to decrease pollution.            