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La Soufrière Saint Vincent eruption: data hubs in action to support scientists

© Pexels

Less than 200 kilometres from Martinique, in the north of the main island of Saint Vincent and the Grenadines, the La Soufrière volcano began an explosive eruption on Friday 9 April. To assist the University of West Indies – Seismic Research Centre (UWI-SRC) in charge of managing the crisis, geophysicists at the IPGP Earth physics institute in Paris and the LOA atmospheric optics laboratory in Lille, with support from the ForM@Ter and AERIS data hubs, analysed a combination of high-resolution optical, radar and weather satellite imagery to keep track of the volcano’s activity.

On the morning of 9 April, La Soufrière Saint Vincent volcano began a first explosive eruption at around 8:45 local time. After a lull of five hours, a long explosive phase spewed vast quantities of ash into the atmosphere for 10 hours non-stop, followed by massive explosions and devastating pyroclastic lava flows.

Several instruments observing volcanic activity on the ground were destroyed or rendered inoperable by the harsh conditions. Space-based remote sensing would therefore play a crucial role in monitoring the situation.

Characterizing volcano emissions in real time

The AERIS data hub focused on meteorological data from geostationary satellites

Teams at the AERIS/ICARE data and services hub sprang into action to provide analyses centred on the volcano in near-real time (+30 minutes) based on data from the GOES-16 weather satellite. These images acquired every 10 minutes enabled them to keep track of the eruption. The data were made available via a dedicated page on ICARE’s website.

Figure 1: Animation on the AERIS/ICARE VOLCPLUME platform of the dispersion of the ash plume from La Soufrière based on S5P/TROPOMI satellite observations of the integrated SO2 column (in Dobson units (DU)) from 9 to 17 April. The plume passed over areas equipped with AERONET (AErosol RObotic NETwork) photometry stations, shown by squares with the colour indicating the mean daily aerosol optical depth (AOD).

The ForM@Ter data hub and DINAMIS unit focused on the volcano with optical imagery

The ForM@Ter data and services hub’s CIEST² new-generation scientific and technical expertise and response unit was activated on 9 April at 8:00 UTC at the request of the IPGP Earth physics institute in Paris. This unit was able to task the first acquisitions of high-resolution optical imagery by the Pleiades satellites (Airbus ADS/CNES) barely two hours after the volcano had erupted, thanks to Data Terra’s DINAMIS structure (Dispositif National d’Approvisionnement Mutualisé en Imagerie Satellitaire*).

* National structure for shared procurement of satellite imagery

These images revealed a crater around 600 metres across and at least 100 metres deep. Pleiades’ high spatial resolution also made it possible to discern a layer of ash more than 100 metres thick and the valleys cutting into the summit of the volcano filled with pyroclastic lava flows.

Figure 2: Top left: view of the volcano before the eruption (Google Earth – Digital Globe 2017). Bottom left: radar image acquired at the height of the eruption (Copyright 2021 Capella Space, All Rights Reserved). The inset shows Pleiades optical images acquired a few minutes apart, indicating zero visibility. Right: Pleiades image of 15 April 2021, providing a first situational picture between clouds during a lull in activity. © Airbus DS / CNES (2021)

Monitoring a volcano eruption: natural scientific synergies

Characterizing volcanic processes in real time using satellite data is essential to gain a clearer understanding and anticipate their impacts on the ground and on air quality. In this kind of situation, space-based remote sensing is a precious aid for observatories and civil protection teams, helping them to formulate better recommendations and base decisions on a wider range of observable variables. Combining different types of observations calls for synergistic resources and analyses across several international communities, in the fields of solid Earth, atmospheric and land surfaces science. This volcano crisis is a fine example of an international, interdisciplinary effort by multiple organizations, confirming that the study and monitoring of volcanos and eruptions cuts across different areas of science. Such interdisciplinary cooperation must naturally be achieved working closely with volcanologists doing monitoring in the field.

The Data Terra research infrastructure encourages and develops integrated approaches that cut across the components of the Earth system.

Science contacts

➡️ Marie Boichu, LOA atmospheric optics laboratory (Villeneuve d’Ascq): marie.boichu@univ-lille.fr
➡️ Raphaël Grandin, IPGP Earth physics institute, Paris: grandin@ipgp.fr