A Near Real-Time and Free Tool for the Preliminary Mapping of Active Lava Flows during Volcanic Crises: The Case of Hotspot Subaerial Eruptions

Abstract

Monitoring the evolution of lava flows is a challenging task for volcano observatories, especially in remote volcanic areas. Here we present a near real-time (every 12 h) and free tool for producing interactive thermal maps of the advance of lava flows over time by taking advantage of the free thermal data provided by FIRMS and the open-source R software. To achieve this, we applied two filters on the FIRMS datasets, one on the satellite layout (track) and another on the fire radiative power (FRP). To determine the latter, we carried out a detailed statistical analysis of the FRP values of nine hotspot subaerial eruptions that included Cumbre Vieja-2021 (Spain), Fagradalsfjall-2021 (Iceland), LERZ Kilauea-2018 (USA), and six eruptions on the Galápagos Archipelago (Ecuador). We found that an FRP filter of 35 ± 17 MW/pixel worked well at the onset and during the first weeks of an eruption. Afterward, once the cumulative statistical parameters had stabilized, a filter that better fit the investigated case could be obtained by running our statistical code. Using the suggested filters, the thermal maps resulting from our mapping code have an accuracy higher than 75% on average when compared with the official lava flow maps of each eruption and an offset of only 3% regarding the maximum lava flow extension. Therefore, our easy-to-use codes constitute an additional, novel, and simple tool for rapid preliminary mapping of lava fields during crises, especially when regular overflights and/or unoccupied aerial vehicle campaigns are out of budget.

Implications for Shallow Magma Transfer During the 2017 and 2018 Eruptions at Fernandina (Galápagos) Inferred From InSAR Data

“…Further details on the 2017 and 2018 eruptions at Fernandina are reported in Vasconez et al (2018). Finally, the 2018 eruption was followed in January 2020 by a circumferential eruption near the eastern caldera rim (Bernard et al, 2022;Vasconez et al, 2022).…”

“…(2018). Finally, the 2018 eruption was followed in January 2020 by a circumferential eruption near the eastern caldera rim (Bernard et al., 2022; Vasconez et al., 2022).…”

Complex paths of magma propagation at Fernandina (Galápagos): The coexistence of circumferential and radial dike intrusion during the January 2020 eruption

“…From 2017 to 2020, three closes in time eruptions occurred at Fernandina: a circumferential eruption near the SW caldera rim in September 2017, a radial eruption on the north ank in June 2018 and a circumferential eruption near the E caldera rim in January 2020 (Fig. 1b; Bernard et al, 2022;Vasconez et al, 2022;Galetto et al, 2023b). This latter eruption, characterized by lava ow emission, started on January 12 and ended the day after (Bernard et al, 2022).…”

Lava Flow Mapping Using Sentinel-1 SAR Data at the Fagradalsfjall Volcano, Iceland

“…They also manually mapped the lava flow, and calculated lava volume and effusion rates. Another study mapped the 2021 lava paths in the Fagradalsfjall volcanic system using data provided by the Fire Information for Resource Management System (FIRMS) (Vasconez et al, 2022). SAR data have been used for volcanic monitoring, deformation analysis, and lava flow mapping of various volcanic eruptions, including the 2014-2015 Holuhraun eruption in Iceland (Dumont et al, 2018;Pedersen et al, 2017), the 2017-2018 unrest at Mount Agung in Indonesia (Albino et al, 2020), the 2011-2013 and 2018 Kilauea eruptions in Hawaii (Lee, Jung, & Hong, 2023;Poland et al, 2014), and the 2014-2015 Fogo eruption in Cabo Verde (Tiengo et al, 2021).…”