David Noone, Oregon State University (IMAGE) Oregon State University Caption David Noone in a snow pit that reveals layers of snow that pile up one after another as different snow storms pass Summit Station, Greenland. Dark and light layering gives evidence of evaporation and refreezing of water vapor. Credit Oregon State University 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.