NASA recently completed an in depth study of the levees and wetlands along the Louisiana Gulf Coast. Two aircraft, equipped with special surveying instruments were used; a C-20A and a King Air B200.
“This was a great opportunity to use instruments that work together to create a more complete picture of the changing Louisiana delta,” said Randall Friedl, manager of the Earth System Science Formulation Office at NASA’s Jet Propulsion Laboratory (JPL), Pasadena, California.
The marshlands are vitally important; they serve as a natural barrier between land and sea and are home to a delicate ecosystem. The natural barrier is crucial for keeping heavily populated areas safe by slowing down the influx of water that occurs during storms and hurricanes. The wetlands protective abilities are diminished by rising sea levels and dying vegetation; meaning increased jeopardy for local communities and economy during disasters. Due to the difficulty of ground-based travel in this constantly changing region, air flight is key for surveying operations.
The surveying instruments included:
- The Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), an imaging radar which measures how locations change between repeat flights over the same path. (The C-20A flew with this one)
- The Next-Generation Airborne Visible/Infrared Imaging Spectrometer (AVIRISng), which obtains accurate quantitative characterizations of the composition and features of Earth by observing changes in light reflected from the surface. (The King Air B200 carried this instrument)
- The Air Surface and Ocean Topography (AirSWOT) instrument, an airborne prototype of a planned spaceborne precision radar that employs a cutting edge technique to measure changes over time in Earth’s water surfaces. (The King Air B200 carried this one as well)
Friedl noted that the aircraft’s equipped instruments work in harmony to characterize key wetland properties. This includes the extend of flooding, seasonal flooding dynamics and even vegetation type. The research provides data to federal and local agencies, which use the information to determine the best way to allot resources for combating the negative effects of wetland loss and floods. The information is also vital for improving delta land building modeling which can be applied to help restore deltas worldwide.
The C-20A and King Air B200, (both based at NASA’s Armstrong Flight Research Center facility in Palmdale, Calfornia), flew with their specially equipped instruments over the Wax Lake Delta; noteworthy for being one of the few deltas in the world growing through natural sedimentation processes.
“Most deltas are highly engineered, inhabited areas that are in danger from a combination of subsidence and sea level rise. This happens because dams upstream and levees in the delta prevent the natural process of sedimentation from offsetting subsidence,” said Cathleen Jones of JPL, UAVSAR Principal Investigator.