"The carbon dioxide from airplanes accounts for about 3 percent of the world’s greenhouse gas emissions, a share projected to go up as air traffic rises. The European Union is now requiring airlines that fly into or out of Europe to pay a fee for these emissions. This is a smart response to an urgent problem. The United States and the other nations opposing the program should either come up with a better idea — soon — or drop their objections." (Quoted from article)