Greenland Ice Core (IMAGE) University of Washington Caption Becky Alexander in the cold room of the UW’s IsoLab with ice drilled from an ice sheet that preserves atmospheric conditions from previous centuries. Her team analyzed an ice core from central Greenland to show that emissions from photosynthetic marine organisms appear stable since the mid-1800s. Credit Mark Stone/University of Washington Usage Restrictions With credit License Original 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.