Digital Elevation Models (DEMs) after the Shovi (Caucasus) debris flow, 13 August 2023

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Introduction
On 4 August 2023, a large debris flow struck the mountain resort town of Shovi in Georgia. More on this event here : https://eos.org/thelandslideblog/the-4-august-2023-debris-flow-at-shovi-in-georgia
Two Pléiades stereo images were acquired after the event on 13 August 2023, thanks to the activation of the CIEST² (https://www.poleterresolide.fr/ciest-2-nouvelle-generation-2/) scheme.
We share here the Pléiades DEMs derived from these images. The collection includes four files:
Shovi_2023-08-13a_DEM_2m.tif
Shovi_2023-08-13a_DEM_20m.tif
Shovi_2023-08-13b_DEM_2m.tif
Shovi_2023-08-13b_DEM_20m.tif
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Methods
The Pléiades stereo-images were processed using the Ames Stereo Pipeline (ASP, Beyer et al., 2018), yielding a DEM in 2x2m and 20x20 m GSD and an orthoimage in 0.5x0.5m GSD. The processing was done using as only input the stereo-images and their orientation information, as Rational Polynomial Coefficients (RPCs). The parallel_stereo routine performs all the steps needed in the correlation of the stereo-images, yielding a pointcloud which is then interpolated using the routine point2dem. We used the semi global matching algorithm and the set of processing parameters from Deschamps-Berger et al. (2020)
Beyer, R. A., Alexandrov, O., and McMichael, S.: The Ames Stereo Pipeline: NASA's Open Source Software for Deriving and Processing Terrain Data, Earth and Space Science, 5, 537–548, https://doi.org/10.1029/2018EA000409, 2018.
Deschamps-Berger, C., Gascoin, S., Berthier, E., Deems, J., Gutmann, E., Dehecq, A., Shean, D., and Dumont, M.: Snow depth mapping from stereo satellite imagery in mountainous terrain: evaluation using airborne laser-scanning data, The Cryosphere, 14, 2925–2940, https://doi.org/10.5194/tc-14-2925-2020, 2020.===========================
Data Specifications:
Cartographic projection: UTM zone 38N (EPSG:32638)
Origin of Elevation: meters above WGS84 ellipsoid
Raster data format: GeoTIFF
NoData value : -9999
Pléiades dataset includes only DEMs because a licence needs to be signed with CNES to access Pléiades imagery. Please contact the authors for further information on this.
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Acknowledgements: 
Pléiades images were provided under the CIEST² initiative (CIEST2 is part of ForM@Ter (https://en.poleterresolide.fr/) (Pléiades © CNES 2023, distribution AIRBUS DS)
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Dataset Attribution:
This dataset is licensed under a Creative Commons CC BY-NC 4.0 International License (Attribution-NonCommercial).
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Citation:
Please cite this repository as described below:
Etienne Berthier. (2023). Digital Elevation Models (DEMs) after the Shovi flood (Caucasus), 13 August 2023