You must have a javascript-enabled browser and javacript and stylesheets must be enabled to use some of the functions on this site.


Small Baseline DIFSAR Techniques for Earth Surface Deformation Analysis

Riccardo Lanari(1) and Eugenio Sansosti(1)

(1) I.R.E.A. (CNR), via Diocleziano 328, 80124, Napoli, Italy


Differential Synthetic Aperture Radar Interferometry (DIFSAR) is a remote sensing technique that allows us to produce spatially dense deformation maps with centimeter to millimeter accuracy. An effective way to detect and follow the temporal evolution of deformations is via the generation of time-series; to do this, the information available from each interferometric data pair must be properly related to those included in the other acquisitions, via the generation of an appropriate sequence of DIFSAR interferograms. In this context an innovative algorithm referred to as Small Baseline Subsets (SBAS) approach, has been recently proposed [1]. It relies on the use of small baseline differential SAR interferograms (to mitigate decorrelation phenomena) and on the application of the singular value decomposition (SVD) method in order to link independent SAR acquisition data sets, separated by large baselines, thus increasing the number of data used for the analysis. The SBAS algorithm, originally developed to investigate spatially extended deformation phenomena has been recently extended to analyze localized displacements that may affect, for example, small areas or single buildings [2]. The availability of both large and small scale information allows us to deeply investigate the deformation behavior of the studied zones. In this work we present the results achieved by applying the SBAS approach to data acquired by the European Remote Sensing (ERS) satellites in last decade. Several test sites of scientific interest have been considered, such as the Napoli Bay (including the Campi Flegrei caldera and the Somma-Vesuvius volcanic complex), the Etna volcano area and the Los Angeles zone in Southern California. The proposed results demonstrate the effectiveness of the approach. Moreover, it is also discussed a multi-platform DIFSAR approach for combining ERS and ASAR ENVISAT data; this solution should allow us to significantly extend the temporal analysis of the detected deformations by benefiting of the future availability of ASAR data.

References [1] P. Berardino, G. Fornaro, R. Lanari, E. Sansosti: “A new Algorithm for Surface Deformation Monitoring based on Small Baseline Differential SAR Interferograms”, IEEE Transactions on Geoscience and Remote Sensing, Vol. 40, No. 11, pp. 2375-2383, November 2002. [2] P. Berardino, G. Fornaro, R. Lanari, M. Manunta, M. Manzo, A. Pepe and E. Sansosti: “A Two-Scale Differential SAR Interferometry Approach for Investigating Earth Surface Deformations”, Proc. IGARSS, Toulouse, France, July 2003, Vol. 2, pp. 1184 – 1186.


Full paper

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry