Many scientists regard the sharp decline in reef health as alarming. United Nations-sponsored research estimates that 20 percent of the world's coral structures have died or become badly damaged in the past 20 years and that most of the world's coral could be similarly threatened in the next 50 years. The Landsat images represent a major shortcut in the costly, time-consuming process of monitoring reefs. We need to use remote sensing to help fight for their conservation. The scientists say they have already archived 5,000 images from over 2,000 coral reefs.
Coral exists throughout the world's tropical oceans.
Pollution and damage from ship traffic have long presented a threat to coral reef health. But reef organisms are notoriously sensitive to changes in water temperature, and rising seawater temperatures believed to be linked to global warming have triggered a dramatic rise in the rate of coral decline in the last two decades. The recent strong cycle of storms and weather changes linked to the El Nino and La Nina phenomena are also believed to have harmed coral reefs in many parts of the world. The NASA team, composed of scientists from the University of South Florida, the College of Charleston in South Carolina and Dalhousie University in Nova Scotia, presented its research at the ninth annual Coral Reef Symposium in Indonesia this week. All Rights Reserved.