Scientists believe that there is only so much that the Earth can take in terms of Carbon Dioxide. There is a worldwide effort to reduce this emission and replace it with green sources of energy. But sometimes this effort is more of a perception than a reality. As an example, places like Oregon which is considered as green as a state could be, is actually not contributing to a worldwide reduction in Carbon Dioxide since their internal efforts are offset by the fact that they export coal that will eventually be burnt in other countries. So, in the end of the day the state is still generating directly or indirectly the same amount of Carbon Dioxide.