Ship Tracks off Alaska Coast (image) DOE/Pacific Northwest National Laboratory Caption Ship exhaust creates long streaks of clouds across the ocean's dark surface, making the sky brighter and reducing the amount of heat trapped in the atmosphere. Some researchers are exploring ways to make clouds brighter to reflect more sunlight back into space. Credit Photo courtesy of NASA. http://earthobservatory.nasa.gov/IOTD/view.php?id=37455 Usage Restrictions Credit NASA 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.