Digital Elevation Models (DEMs) and lava outlines from the Litla-Hrútur eruption, Iceland, July 2023

• Main Authors: Joaquin M.C. Belart, Virginie Pinel, Etienne Berthier, Sydney R. Gunnarson
• Format: Other/Unknown Material
• Language: English
• Published: Zenodo 2023
• Subjects: DEM; Volcano; Emergency tasking; Iceland
• Online Access: https://doi.org/10.5281/zenodo.8156385

Introduction: On the 10th of July 2023, at 16:40, an eruption started in the Reykjanes Peninsula, Iceland, next to the mountain "Litla-Hrútur". As part of the response, the CIEST 2 french initiative was activated (Gouhier et al., 2022). Once activated, Pléiades stereoimages were tasked and scheduled for fast delivery within the area of Interest. Once acquired and delivered, the Pléiades images are processed following the methods described in the section below. This repository contains the near-real time results of DEMs, difference maps compared to a pre-eruption DEM, and lava outlines digitized from the difference map and the orthoimage. This repository is currently in construction and will be updated during the time period where the Pléiades stereoimages are being acquired. Methods : The Pléiades stereoimages were processed using the Ames StereoPipeline (ASP, Shean et al., 2016, see ASP branch in repository), yielding a DEM in 2x2m GSD and an orthoimage in 0.5x0.5m GSD. The processing was done using as only input the stereoimages and their orientation information, as Rational Polynomial Coefficients (RPCs). The parallel_stereo routine performs all the steps needed in the correlation of the stereoimages, yielding a pointcloud which is then interpolated using the routine point2dem . Besides default parameters, the parallel_stereo parameters used for creation of the DEMs were the standard parameters, plus the following ones: --stereo-algorithm asp_mgm--corr-tile-size 300 --corr-timeout 900 --cost-mode 3 --subpixel-mode 9 --corr-kernel 7 7 --subpixel-kernel 15 15 Once the DEM was created, DEM co-registration was applying in order to align and minimize positional biases between the pre-eruption DEM and the Pléiades DEMs. We followed the co-registration method of Nuth & Kääb (2011), implemented by David Shean’s co-registration routines ( https://github.com/dshean/demcoreg , Shean et al., 2016). The co-registration involved a horizontal and vertical shift of the Pléiades DEMs, as well as a planar tilt correction. ...