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NASA post-hurricane Katrina images available on Google Earth

When Hurricane Katrina made landfall in August 2005, it changed the look of some of the coastlines of three U.S. states. Now, using Google Earth's software on the Internet, people can see the before and after affects, thanks to detailed images from NASA and the U.S. Geological Survey (USGS). Credit: USGS

NASA and the U.S. Geological Survey (USGS) have published detailed aerial imagery of the impact of Hurricane Katrina on the Internet viewable on Google Earth. The images show changes that Katrina made to the Gulf coast from Panama City, Fla. to New Orleans, La. The general public can now go online and see before and after images of Katrina's wrath.

Hurricane Katrina made landfall in south Plaquemines Parish, La., near the towns of Empire, Buras and Boothville, on the morning of Aug. 29, 2005. It caused widespread destruction in Louisiana, Mississippi, and Alabama and was the most expensive hurricane in United States history, causing an estimated $80 billion in damages, according to the National Oceanic and Atmospheric Administration. Katrina was the deadliest U.S. hurricane since 1928, claiming at least 1,300 lives.

The coastlines of these three Gulf states were changed forever. NASA, using an Atlantic Global Research contract aircraft and the agency's own advanced technology, made it possible to see the extent and the type of damage that Katrina caused when it came ashore.

The changes to the coasts were cataloged by NASA's Experimental Advanced Airborne Research Lidar mapping system onboard the NASA contract aircraft. This is an airborne lidar that uses a laser to measure distance to a surface once the laser light is reflected back to the instrument. The system is well suited for mapping complex environments including coral reefs, sandy beaches, coastal vegetation and trees. The system includes two digital cameras that take photos every second, or every 50-70 meters (55-76 yards), along the flight path.

These are before and after Hurricane Katrina images of a water park in Gulfport, Mississippi. On the before image (left), the blue wavy lines are the water park slides, with a building to the left of it. In the after image, the water slide and building have been completely demolished and washed away by Hurricane Katrina. Credit: NASA Goddard Space Flight Center

NASA's airborne lidar helps to rapidly assess coastal storm impacts and is part of an ongoing NASA-USGS effort to understand coastal change and provide improved tools to assess the vulnerability of coastal communities, resources, and infrastructure. NASA technology provides for rapid and accurate assessment of coastal conditions before and after storms; supporting USGS research programs and providing critical information for coastal planners and emergency response agencies.

During September 2005, there were five flight days during which roughly 250,000 photos were taken. The photos, which show features as small as 20 centimeters (7.8 inches) across, are viewable at no cost by anyone by accessing Google Earth on the Internet. Some flight lines over Biloxi and Gulfport, Miss., were requested by the Federal Emergency Management Agency (FEMA) to assess the damage Katrina did to the coast.

Charles W. Wright of NASA's Wallops Island Flight Facility, Wallops, Va., the airborne lidar principal investigator, placed the imagery catalog online at Google Earth. "This is the first time that I can remember such an easy-to-use tool putting so much data at the fingertips of so many people with so little effort," Wright said. Initially, those involved with the project were working to bring the lidar data of the New Orleans levees online for FEMA, and had not anticipated that they would be bringing the photography online.

The U.S. Geological Survey's Coastal and Marine Geology Program investigates the extent and causes of coastal impacts of hurricanes and extreme storms on U.S. coasts The program's objective is to improve the capability to predict coastal change that results from severe tropical and extra-tropical storms. Such a capability will help with decision-making for post-Katrina recovery and coastal zone planning; provide assessments of what areas are at risk in the future for extreme coastal changes due to hurricanes.

John Haines, of the USGS program, sees the NASA technology as a revolutionary tool. "NASA has provided sensors, data collection systems and processing tools that dramatically increase our ability to accurately and rapidly provide critical information on impacted coastal settings. The NASA airborne lidar system has been essential to our research efforts to understand and predict coastal vulnerability while meeting the critical data needs of coastal managers."