Automated processing of aerial imagery for geohazards monitoring: Results from Fagradalsfjall eruption, SW Iceland, August 2022

• Main Authors: Sydney R. Gunnarson, Joaquín M. C. Belart, Birgir V. Óskarsson, Magnús Tumi Gudmundsson, Thórdís Högnadóttir, Gro B. M. Pedersen, Tobias Dürig, Virginie Pinel
• Format: Dataset
• Language: English
• Published: 2023
• Subjects: Photogrammetry; Iceland; Remote Sensing; Volcano Monitoring; DEM; Orthomosaic; Pléiades; Pedersen
• Online Access: https://zenodo.org/record/7871187; https://doi.org/10.5281/zenodo.7871187

1- Dataset Summary Here we present a dataset of DEMs (Digital Elevation Models), orthomosaics, and lava area outlines for the August 2022 eruption at Fagradalsfjall, SW Iceland. The dataset consists of: (1) five aerial surveys collected over the course of the August 2022 Fagradalsfjall eruption, (2) one survey carried out on 14 August 2022 using Pléiades satellite stereo images, and (3) a larger aerial survey, covering the 2021 and 2022 eruption sites in late September 2022 after the volcanic activity concluded. 2- Background The volcano at Fagradalsfjall, SW-Iceland, began erupting on 3 August 2022 at 13:20 following 10 months of quiescence. As part of the response plan, a series of photogrammetric surveys were conducted in rapid, operational mode throughout the duration of the eruption. Subsequent production of data products for natural hazards monitoring (lava maps, lava volumes, effusion rates) were calculated within hours and reported to the Icelandic Civil Defense, following a similar approach that described in Pedersen et al., 2022a and in Gouhier et al., 2022. At the start of the 2022 eruption, GCPs had not yet been placed around the new fissure, but reference data (orthomosaics and DEMs) which had been georeferenced using targets measured with differential GNSS existed of the eruption site from September 2021 from Pedersen et al. (2022b) were available to use as a reference in the new workflow instead of GCPs. Due to the urgent need from authorities for information about the new eruption, a processing method that avoids the time-consuming task of manual GCP selection using a reference image for georeferencing was preferable in this instance. Besides the acquisition of aerial photographs, the CIEST2 initiative was also re-activated to collect Pléiades stereo images in emergency mode (Gouhier et al., 2022). 3 – Overview of data collection Table 1 contains the overview of the surveys collected and presented in this repository. Table 1. Summary of surveys included in this dataset, by survey date. Date & ...