Search

The ever‐increasing amount of Synthetic Aperture Radar (SAR) data motivates the development of automatic processing chains to fully exploit the opportunities offered by these large databases. The Synthetic Aperture Radar Interferometry (InSAR) Mass processing Toolbox for Multidimensional time series is an optimized tool to automatically download SAR data, select the interferometric pairs, perform the interferometric mass processing, compute the geocoded deformation maps, invert and display the velocity maps and the 2D time series on a web page updated incrementally as soon as a new image is available. New challenges relate to data management and processing load. We address them through methodological improvements dedicated to optimizing the InSAR pair selection. The proposed algorithm narrows the classical selection based on the shortest temporal and spatial baselines thanks to a coherence proxy and balances the use of each image as Primary and Secondary images thanks to graph theory methods. We apply the processing to three volcanic areas characterized with different climate, vegetation, and deformation characteristics: the Virunga Volcanic Province (DR Congo), the Reunion Island (France), and the Domuyo and Laguna del Maule area (Chile‐Argentina border). Compared to pair selection based solely on baseline criteria, this new tool produces similar velocity maps while reducing the total number of computed differential InSAR interferograms by up to 75%, which drastically reduces the computation time. The optimization also allows to reduce the influence of DEM errors and atmospheric phase screen, which increase the signal‐to‐noise ratio of the inverted displacement time series. Plain Language Summary: Development of satellite remote sensing greatly helps to mitigate natural hazard in remote or dangerous areas like volcano‐tectonic regions or landslide‐prone regions. In particular, Synthetic Aperture Radar Interferometry (InSAR) offers the possibility to measure ground surface displacements with millimeter resolution. Several methods exist to benefit from the large amount of data to perform time series of ground deformation with sub‐centimeter resolution. However, the ever‐increasing number of available images poses new challenges (e.g., to process the large amount of data, to manage large databases and to extract useful information in near‐real time for operative purposes). Mass processing Toolbox for Multidimensional time series (MasTer) is a fully automatic tool able to provide updated velocity maps and displacement time series resulting from the processing of satellites radar images, which are regularly acquired by space agencies. Hereby, we present a methodological development to speed up the processing and improve the signal‐to‐noise ratio of the obtained ground deformation time series. This is achieved by optimizing the InSAR pair selection. By also reducing the storage space and raw‐memory requirements, it allows processing longer time series with the same computational infrastructure. The proposed algorithm, written in Python, is included in the MasTer toolbox, though it can easily be adapted for other time series software. Key Points: Proposed optimized pair selection improves Synthetic Aperture Radar Interferometry time series quality while reducing computation time and memory requirementsProposed coherence proxy allows pair and image rejection without computing the interferogramsAlgorithm written in Python is used for automatic processing with Mass processing Toolbox for Multidimensional time seriestoolbox and applicable to other time series software [ABSTRACT FROM AUTHOR]

Copyright of Revue Francaise de Photogrammetrie et de Teledetection is the property of Societe Francaise de Photogrammetrie et de Teledetection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)