Integration of InSAR Time-Series Analysis and Water-Vapor Correction for Mapping Postseismic Motion After the 2003 Bam (Iran) Earthquake

• Published in: IEEE transactions on geoscience and remote sensing Vol. 47; no. 9; pp. 3220 - 3230
• Main Authors: Zhenhong Li, Fielding, E.J., Cross, P.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.09.2009; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied geophysics; Atmospheric modeling; Bam earthquake; Clouds; Deformable models; Delay estimation; Earth sciences; Earth, ocean, space; Earthquakes; Earthquakes, seismology; Exact sciences and technology; interferometry; Internal geophysics; MERIS; Motion analysis; postseismic motion; Radar scattering; Standard deviation; synthetic aperture radar (SAR); Synthetic aperture radar interferometry; time series (TS); Time series analysis; water-vapor effects; Middle East; Iran; Asia; time series analysis; models; interferometry; remote sensing; cartography; baseline; clouds; Bam earthquake; earthquakes; water-vapor effects; synthetic aperture radar (SAR); water vapor; postseismic motion; time series (TS); deformation; atmospheric correction; reduction; correlation coefficient; Synthetic aperture radar; standard deviation
• ISSN: 0196-2892; 1558-0644
• DOI: 10.1109/TGRS.2009.2019125

Atmospheric water-vapor effects represent a major limitation of interferometric synthetic aperture radar (InSAR) techniques, including InSAR time-series (TS) approaches (e.g., persistent or permanent scatterers and small-baseline subset). For the first time, this paper demonstrates the use of InSAR TS with precipitable water-vapor (InSAR TS + PWV) correction model for deformation mapping. We use MEdium Resolution Imaging Spectrometer (MERIS) near-infrafred (NIR) water-vapor data for InSAR atmospheric correction when they are available. For the dates when the NIR data are blocked by clouds, an atmospheric phase screen (APS) model has been developed to estimate atmospheric effects using partially water-vapor-corrected interferograms. Cross validation reveals that the estimated APS agreed with MERIS-derived line-of-sight path delays with a small standard deviation (0.3-0.5 cm) and a high correlation coefficient (0.84-0.98). This paper shows that a better TS of postseismic motion after the 2003 Bam (Iran) earthquake is achievable after reduction of water-vapor effects using the InSAR TS + PWV technique with coincident MERIS NIR water-vapor data.