Imaging the Devastation

January 18, 2005 Issue

These simulated natural color images show a stretch of coast on the island of Phuket, Thailand, a major tourist destination hit by last month’s tsunami. Along Thailand’s Andaman Sea coast, more than 4,300 people were confirmed dead in the disaster, as of Dec. 30, and thousands more were still missing. The image on the right was taken Dec. 31, and that on the left is from two years earlier. The changes along the coast—the vegetation has been stripped away—are obvious. The images were taken by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), a satellite-based imaging instrument, and put together by Michael Ramsey, an assistant professor in Pitt’s Department of Geology and Planetary Science and a member of ASTER’s science team. Ramsey and others on the team are collecting image data of tsunami-devastated areas. “For the past two weeks, we’ve just really been imaging the heck out of the area and crunching the data,” he said. At a resolution of 15 meters, the scientists can get a close look and at the same time do a complete survey of how much land mass was affected. “We can look at habitat destruction—how many trees, how much area was lost,” said Ramsey. They can also view images in three dimensions, in effect, by taking pictures in two different directions; this will allow them to measure vertical changes in the beaches and inland areas. More ASTER images can be found online at http://asterweb.jpl.nasa.gov.