Ragweed Distribution in the 2050s (IMAGE) University of Washington Caption By the 2050s, under a high-emissions scenario the bright blue areas will be newly populated with ragweed according to most climate models, and orange areas will have significantly less ragweed according to most climate models. Lighter blue shows that some of the 13 climate models predict expansion, while brown shows that some of the models predict a contraction. Gray is where ragweed is not present, and black indicates no change. Credit Michael Case/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.