Factors (IMAGE) University of Washington Caption The projections are based on statistical analysis of world population (green), gross domestic product (purple) and carbon intensity (brown). This last factor turns out to have the biggest impact on future carbon emissions. Credit Adrian Raftery/University of Washington Usage Restrictions With credit 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.