Climate Reconstructions (IMAGE) University of Maryland Caption This graph shows global mean rates of temperature change over the last 2,000 years, as determined by a new reconstruction based on climate proxy data. Red denotes temperature increases while blue denotes temperature decreases. The green line shows the maximum expected warming rate without human influence; the dashed orange line signifies the ability of climate models to simulate this natural upper limit. The black line indicates average global as determined by direct measurements since the Industrial Revolution. Credit University of Bern Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.