Measurements of Cloud Condensation Nuclei (IMAGE) The Hebrew University of Jerusalem Caption This is a picture of the measurements of cloud condensation nuclei collected at the Amazon Tall Tower Observatory in the middle of the Amazon Basin. Such ground-truth data are essential for the validation of the satellite measurements. Credit Meinrat O. Andreae 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.