Oxygen at Bottom of the World (IMAGE) Columbia Climate School Caption Researchers have found that bottom waters of the Southern Ocean had very low levels of oxygen during the last ice age, indicating high uptake of carbon. Here, dissolved Southern Ocean bottom-water oxygen in modern times. Brighter colors indicate more oxygen; dots show sites where researchers sampled sediments to measure past oxygen levels. Credit Jaccard et al., <i>Nature</i> 2016 Usage Restrictions Credit must be given. 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.