HR: 16:00h
AN: G54A-01 INVITED    [Abstracts]
TI: Properties of L-band interferograms derived from ALOS/PALSAR radar observations
AU: * Zebker, H A
EM: zebker@stanford.edu
AF: Dept. of Geophysics, Stanford University, Stanford, CA 94305-2155, United States
AU: Rosen, P A
EM: paul.rosen@jpl.nasa.gov
AF: Jet Propulsion Laboratory California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, United States
AU: Hager, B
EM: brad@chandler.mit.edu
AF: Earth, Atmosphere, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
AB: We present here L-band radar interferograms derived from ALOS/PALSAR satellite observations over several different Earth surface terrains. These InSAR images are representative of data that would be collected by the proposed DESDynI radar mission. We have examined interferograms over Hawaii, Greenland, Egypt, and California, which present surfaces covered by light vegetation, dense tropical forests, vegetation-free desert, and many ice facies. The interferograms exhibit very high correlation when compared to the C-band radar data commonly available from other existing satellites, yielding improved spatial coverage and reliable temporal sampling. In many cases the acquisitions are fully polarimetric, so that we can compare how the polarization state affects the statistics of the interferometric echoes. Specific results to date show that the use of L-band data rather than C-band permits much more comprehensive deformation modeling of rift events in Hawaii and of creep along faults, with little difference between interferograms formed from co- and cross-polarized returns. Ice from the wet snow, percolation, and dry snow zones in Greenland often correlates well (>50%) even with the PALSAR six-week repeat interval. Observable fringe patterns are seen in the Hawaiian rain forest in many locations over this same orbit interval. Interferograms derived from HH and VV data over ice and vegetation are very similar, and HV InSAR data are similarly correlated when allowance is made for the lower signal to noise ratio, even though considerable volume scatter occurs. Cross-interferograms show that the HH return is rather uncorrelated with the VV return, but that a small shift in the mean phase is present in HH-HV difference interferograms. This could be due to a real several cm shift in the phase center of the echo, but we are currently considering whether this apparent phase shift results from cross-polarized contamination of the radar return. With more frequent repeat observations than are possible with ALOS, but with an otherwise similar instrument, the principal science objectives for an InSAR mission as recommended by the National Research Council can be attained.
DE: 0758 Remote sensing
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 1241 Satellite geodesy: technical issues (6994, 7969)
DE: 1294 Instruments and techniques
DE: 1621 Cryospheric change (0776)
SC: Geodesy [G]
MN: 2007 Fall Meeting