Scientists studying the aftermath of Hurricane Georges on coastal areas in Louisiana are using NASA images to help them understand where sand moved and how vegetation was impacted by salt water on two coastal barrier islands and the Atchafalaya River Delta.
Scientists are particularly interested in images of the Chandeleur Island chain because of the severe damage caused by Hurricane Georges in October 1998.
The images were gathered by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) onboard a National Oceanic and Atmospheric Administration (NOAA) plane on October 28. AVIRIS was built and is managed by the Jet Propulsion Laboratory. The instrument measures 224 spectral channels which means it can give scientists a highly detailed look at what is happening on the surface in ways that are invisible to the naked eye.
"The damage from Hurricane Georges on the Chandeleurs Islands was as bad as that of Hurricane Camille almost 30 years ago," said Dr. Shea Penland, a scientist at the University of New Orleans. "Having the chance to use imagery from the AVIRIS scanner gives us a great opportunity to understand the full extent of the hurricane's damage and look at ways to deal with the damage. The AVIRIS data are so rich in imagery and the resolution is so good that we have for the first time the ability to completely characterize the landcover on Louisiana's barrier islands."
"Imaging spectroscopy is a technique that represents a fundamental new way of doing remote-sensing. We are measuring in detail how light is absorbed or reflected by various materials on Earth's surface and that gives us an accurate picture of what those materials on the ground are made of and how the surface is changing," said Robert Green, the AVIRIS experiment scientist at JPL.
NOAA and university scientists believe they will be able to use the imagery to study Louisiana's coastal wetlands, such as the Chandeleurs Islands, to gain a much better understanding how they function and react to outside forces such as storms. The university, NOAA and JPL will also be offering the data to other scientists conducting coastal habitat research on a wide variety of issues, including marine fish habitat conservation and coastal wetlands restoration. People who live on or near the Louisiana bayous protected by these barrier islands, along with those who make their living from the bountiful natural resources of the Mississippi delta, will be the ultimate beneficiaries of the information that is expected to be learned from this extensive data.
"Normally, AVIRIS is flown by NASA at an altitude of 20 kilometers (about 70,000 feet)" said Commander Grady Tuell, project manager of the Remote Sensing Division of NOAA's National Geodetic Survey. "However, both NOAA and NASA felt the instrument could be a very important diagnostic tool if flown at low altitudes and over areas such as the Chandeleurs. At about 3 kilometers (10,000 feet), the resolution is very high."
AVIRIS images of the Atchafalaya Delta show a large tract of newly created wetlands from the recently completed Big Island/Atchafalaya Sediment Delivery Projects. The projects were built with funding from the Coastal Wetlands Planning Protection and Restoration Act. The two projects created more than 364 hectares (900 acres) of new wetlands in the Atchafalaya Delta, and are an important habitat for marine fisheries and migratory waterfowl.
"We see AVIRIS as giving us a tremendous new tool in evaluating the results of our restoration projects," said Rollie Schmitten, assistant administrator of NOAA's National Marine Fisheries Service.
The AVIRIS imagery will also be offered to other scientists conducting coastal habitat research on a wide variety of issues, including marine fish habitat conservation and coastal wetlands restoration. The university will receive the AVIRIS imagery from NOAA and JPL and will serve as a technical information center in the analysis of the storm's impact on the Chandeleur Island chain. The public can also view some of the imagery on the Internet at: http://makalu.jpl.nasa.gov (Click on "AVIRIS Low Altitude Deployment" and look for images of Chandeleur, Timbalier and Atchafalaya Bay on the "Quicklook Index.")
"It is a wonderful opportunity for the university to be able to acquire this world class high technology system that will enable our university researchers to partner with national scientists at NOAA and JPL and other environmental experts to study Louisiana's coastal islands and wetlands," said University of New Orleans Chancellor Gregory O'Brien. "In cooperation with other university and community partners, this unique collaborative effort will ultimately help us to protect an ensure the viability of our priceless natural resources by dealing with the ravaging effects of natural disasters."
JPL, a division of the California Institute of Technology, manages the AVIRIS instrument for NASA's Earth Sciences Enterprise, Washington, DC.
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