Model Output of OH (IMAGE) NASA/Goddard Space Flight Center Caption Model output of OH primary production over a 24-hour period in July tracks with sunlight across the globe. Higher levels of OH over populated land are likely from OH recycling in the presence of NO and NO2, which are common pollutants from cars and industry. Credit Credits: NASA / Julie Nicely 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.