Comparative Ice Core Evidence (IMAGE) Ohio State University Caption (A) Decadal averages of O-18 isotopes from low-latitude, high-elevation ice fields are combined for the last 2,000 years. The number of cores contributing to various parts of the 2,000-year record is shown. (B and C) Also shown are the composites for four Tibetan (B) and three Andean (C) cores. (D) These cores are compared to the Northern Hemisphere meteorological observations (red) back to A.D. 1860 (50) and a multiproxy history (blue) back to approximately 200 A.D.(51). Credit Courtesy of Lonnie Thompson, Ohio State University. Usage Restrictions News media only 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.