The Ecological Footprints of Nations (IMAGE) University of California - Berkeley Caption The environmental impacts of high-, middle- and low-income nations fall on other income tiers, as indicated by the footprints. The numbers are in trillions of 2005 international dollars. Credit Thara Srinivasan/UC Berkeley Usage Restrictions Please credit UC Berkeley 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.