LONG TERM TREND (IMAGE) Columbia Climate School Caption Temperatures and atmospheric concentrations of carbon dioxide over the past 66 million years. Bottom numbers indicate millions of years in the past; right-hand numbers, carbon dioxide in parts per million. Hotter colors indicate distinct periods of higher temperatures; deeper blues, lower ones. The solid zigzagging line charts contemporaneous carbon dioxide levels; shaded area around it reflects uncertainty in the curve. Credit Adapted from CenCO2PIP, Science 2023 Usage Restrictions Credit must be given. 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.