The main causes of global warming occur by many factors. The first cause is greenhouse emission which has much release into the atmosphere. As www.epa.gov said “In 2012, U.S. greenhouse gas emissions totaled 6,526 million metric tons of carbon dioxide equivalents” this is a huge numbers of greenhouse emissions. Industries, factories, power plant station, agriculture and livestock are the entire main factors that released greenhouse gas into the air especially, transportation because people turn to use more vehicles in routine life that means the fume of cars is emitted more into the air, moreover, people inhale it everyday. Another one cause is deforestation. Human still deforest and no tend to do less. According to Forestry Department Food and Agriculture Organization of the United Nations “The net loss of the world’s forests is estimated at 7.3 million hectares (18 million acres) per year” that shows how much we lost our Tree. The more trees, the less carbon dioxide in the atmosphere and more the oxygen that why human needed the tree and essential to us.