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This article introduces the extended timing annotation dataset (ETAD) product for Sentinel-1 (S-1) which was developed in a joint effort of German Aerospace Center (DLR) and European Space Agency (ESA). It allows to correct range and azimuth timing of S-1 images for geophysical effects and for inaccuracies in synthetic aperture radar (SAR) image focusing. In combination with the precise orbit solution, these effects determine the absolute geolocation accuracy of S-1 SAR images and the relative collocation accuracy of repeat pass image stacks. ETAD contains the gridded timing corrections for the tropospheric and ionospheric path delays, the tidal-based surface displacements, and the SAR processing effects, all of which are computed for each data taken using standard models from geodesy and auxiliary atmospheric data. The ETAD product helps S-1 users to significantly improve the geolocation accuracy of the S-1 SAR products to better than 0.2 m and offers a potential solution for correcting large-scale interferometric phase variations. The product layout and product generation are described schematically. This article also reports first the results for different SAR techniques: first, the improvement in geolocation accuracy down to a few centimeters by verification of accurately surveyed corner reflector positions in the range–azimuth plane; second, the well-established offset-tracking technique, which is used for systematic ice velocity monitoring of ice sheets and glaciers, where ETAD can reduce velocity biases down to subcentimetric values; and third, the correction of atmospheric phase contributions in wide-area interferograms used for national and European ground motion services. These early results proof the added value of the ETAD corrections and that the product design is well-suited to be integrated into the processing flows of established SAR applications such as absolute ranging of targets, speckle/feature tracking, and interferometry. publishedVersion

In the last five years, the urban development of the city of Limassol has rapidly increased in the sectors of industry, trade, real estate, and many others. This exponentially increased urban development arises several concerns about the aggravation of potential land subsidence in the Limassol coastal front. Forty six Copernicus Sentinel-1 acquisitions from 2017 to 2021 have been processed and analyzed using the Sentinel Application Platform (SNAP) and the Stanford Method for Persistent Scatterers (StaMPS). A case study for the identification and analysis of the persistent scatterers (PS) in pixels in a series of interferograms and the quantity of the land displacements in the line of sight of the Limassol coastal front is presented in this research, with subsidence rates up to about (−5 to 4 mm/year). For the validation of the detected deformation, accurate ground-based geodetic measurements along the coastal area were used. Concordantly, considering that there is a significant number of skyscrapers planned or currently under construction, this study attempts a preliminary assessment of the impact these structures will pose on the coastal front of the area of Limassol.

Reliable and accurate long term geodetic monitoring with SAR requires the installation of either passive corner reflectors or, alternatively smaller active devices. We report our first results using novel off-the-shelf transponders or electronic corner reflectors (ECRs) for geodetic measurements with Sentinel-1 C-band Synthetic Aperture Radar (SAR) data. For this purpose we set up a triangular arrangement consisting of one trihedral corner reflector and two active ECRs at the campus of German Aerospace Center (DLR) in Oberpfaffenhofen, Germany. We describe the practical aspects of such ECRs as well as first radiometric characteristics. Moreover, we present geometric accuracy numbers derived from imaging geodesy, i.e. absolute radargrammetric positioning, as well as from interferometric phase measurements.

In the last five years, the urban development of Limassol City has rapidly increased in the sectors of industry, trade, real estate, and many others. This exponentially increased urban development introduces several concerns about the aggravation of the land subsidence in the Limassol coastal front. Fifty Copernicus Sentinel-1 data from 2017-2021 have been processed and analyzed using the Sentinel Application Platform (SNAP) and the Stanford Method for Persistent Scatters (StaMPS). A case study for the identification and analysis of the elements (PS) in pixels in a series of interferograms, and then, the quantity of the land displacements in the Line of Sight, in the Limassol coastal front, is presented in this research, with the subsidence rates up to about (-5 to 4 mm / year). For the validation of the detected deformation, accurate ground-based geodetic measurements along the coastal area were used. Concordantly, taking into account that there are a significant number of skyscrapers planned to be built, this study attempts a preliminary assessment of the impact these structures will pose on the coastal front of the area of Limassol.

This document represents the ‘Workplan for transfer of knowledge and experience’ (deliverable D.6.1) for the EXCELSIOR project. It focuses on the scope and activities of WP6 ”Knowledge Transfer and Capacity Building”, whose main objective is to coordinate and manage the secondments and workshops that will take place during the entire EXCELSIOR project in order to facilitate knowledge transfer and capacity building with partnering and supporting organisations. The document will provide a workplan of how knowledge transfer and capacity building will take place between the Consortium partners via workshops, seminars and secondments. This plan relies heavily on the extensive work done at the preparation of the project in defining the seminars, workshops and secondments that will take place between the consortium partners. Deliverable D6.1 is closely tied to WP5 ‘ECoE Resources and Infrastructure’, especially T5.4, Installation, training and technical support. As well, the personnel mobility scheme is critical for task T6.2 Secondments and T6.3 Technical Skills Development. This report provides a guideline regarding how knowledge transfer and capacity building take place. This document will change during every reporting period, to reflect any changes, modification, etc. that are necessary for the optimal functioning of the EXCELSIOR project in order to increase our understanding of what is needed to conduct capacity building for the specific sectors of the ECoE. Therefore, the specific secondments and workshops listed in this report are not final and are indicative. This plan focuses on how knowledge and experience will be transferred mainly, but not exclusively, between the Strategic partners of the EXCELSIOR project. Other experts in EO and remote sensing can provide training and workshops to the ECoE through the EXCELSIOR project. It is vital to develop a methodology in order to monitor a yearly mobility scheme workplan for sustainable know-how transfer for each aspect of the thematic sectors addressed by ECoE, with detailed guidelines regarding training and workshops and update this accordingly every reporting period. The workplan will be updated and adjusted following the WP3 yearly analysis on the strategy and targets for research and innovation. A capacity building strategy and secondment methodology needs to be defined for the EXCELSIOR project. The capacity building strategy has two pillars: (a) a backbone programme for systematic long-term capacity building and knowledge transfer of ECoE staff from the expert partners, with a fixed duration and targets, aiming at both research and innovation upscaling; and (b) ad-hoc visits programme for training on specific skills that may become necessary during the course of the project. The present document constitutes the first version of the ‘Workplan for transfer of knowledge and experience’ in the framework of the EXCELSIOR project, dedicated to Task D6.1 ‘Personnel Mobility Scheme’ under work package WP6 ‘Knowledge Transfer and Capacity Building’. D6.1 is delivered at Month 2 and focuses on the training guidelines of the project. Thus, this document will be updated during the first, second, third, fourth and fifth reporting period of the project.