nonetheless, Hansen considered, The Earth system is already showing signs of reacting, Even in the events of "Slow feedbacks" similar to ice sheet changes.The human caused release of increased carbon dioxide into the atmosphere also presents climate scientists with something they've never seen in the 65 million year record of carbon dioxide levels a drastic rate of increase rendering it difficult to predict how rapidly Earth will respond. In periods when carbon dioxide has increased due to natural causes, unsecured credit card debt of increase averaged about.0001 parts per million per year for example, One hundred parts per million every million ages