HR: 17:30h
AN: G54A-07    [Abstracts]
TI: Quantifying INSAR Temporal Decorrelation and its impact on estimation of vegetation structure
AU: * Chapman, B D
EM: bruce.chapman@jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr, Pasadena, CA 91109, United States
AU: Siqueira, P
EM: siqueira@ecs.umass.edu
AF: University of Massachusetts Amherst, Electrical & Computer Engineering, Knowles Engineering Building, Amherst, MA 01003, United States
AU: Hensley, S
EM: scott.hensley@jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr, Pasadena, CA 91109, United States
AU: Ahmed, R
EM: ruahmed@engin.umass.edu
AF: University of Massachusetts Amherst, Electrical & Computer Engineering, Knowles Engineering Building, Amherst, MA 01003, United States
AB: The National Research Council was commissioned by NASA to conduct a decadal survey to assess the strategy NASA should take for Earth science and applications from Space. One of the recommendations of this report is for a mission called 'DESDynI', consisting of an L-band SAR and a laser altimeter, to measure surface and ice sheet deformation, and to measure vegetation structure for ecosystem health. Measuring vegetation structure with an L-band repeat-pass InSAR mission requires that temporal decorrelation between the SAR observations be well understood. In the worst case, temporal decorrelation would exceed the volumetric decorrelation (which may be modeled as a function of the vegetation structure), making accurate vegetation height inversion impossible from the InSAR data. In the best case, non-negligible temporal decorrelation would bias the estimation. In order to quantify InSAR temporal decorrelation over forested areas, the NASA/JPL AIRSAR SAR conducted a comprehensive series of InSAR flightlines in 2004 over the La Selva Biological Reserve, Costa Rica (a mature, well-characterized tropical rainforest), collecting both single-pass and repeat-pass InSAR data at a variety of baselines and temporal separations (0 meters to 200 meters, 20 minutes to 2 weeks). Results of this analysis will be presented. The L-band ALOS PALSAR SAR, launched in 2006, and currently collecting data sets globally, has a 46 day repeat orbit and baselines less than 1km. Data from this mission, as well as from the 1978 Seasat SAR (which had a 3 day repeat for much of the mission) should likewise provide important characterizations of temporal decorrelation over forested regions. Possible observation strategies for DESDynI may have to accommodate temporal decorrelation effects through more frequent observations of areas subject to weather-induced decorrelation, similar to global observation strategies for optical sensors.
DE: 1209 Tectonic deformation (6924)
DE: 1294 Instruments and techniques
DE: 8110 Continental tectonics: general (0905)
DE: 8488 Volcanic hazards and risks
DE: 8494 Instruments and techniques
SC: Geodesy [G]
MN: 2007 Fall Meeting