text: Greenhouse edmissions wither away with the less cars that ride up and down streets. In Paris, the typical smog reaches to about "147 microgram of particulate matter per cubic meter" stated by source two. This makes it harder for traffic to see and causes an unsafe enviornment for walking. Paris was said to have banned half of cars one day and another half the other and the smog was cleared enough to rescind the no car rule. Greenhouse edmissions, like carbon, can cause acid rain, raises the temperature, and can clog up breathing pathways making it unsafe to go outside when the smog is strong. Carbon can be admitted through the fuel of cars. In France, over 50 percent of cars use diesel fuel which causes a greater amount of greenhouse gas edmission. If society can walk or ride bikes to work or school then the amount of automobiles needed will decrease. The lessening number of automobiles can help create a safer and healthier enviornment.