VOLCPLUME : a unique platform for the monitoring and 4D analysis of volcanic plumes

Initially developed at LOA laboratory (Laboratoire d’Optique Atmosphérique de Lille), as part of the VOLCPLUME project, the platform project that has the same name is coordinated by Marie Boichu. It is financed by the French National Research Agency (ANR-15-CE04-0003) and has been more widely developed by the AERIS/ICARE Data and Services Center since the beginning of 2021 in the framework of the AERIS call for projects.

The VOLCPLUME platform

The objective of the VOLCPLUME platform is to automate the joint analysis, in near-real time, of a large panel of ground/satellite remote sensing observations and in-situ air quality monitoring measurements as well as numerical simulations to monitor the temporal and spatial (three-dimensional) evolution of volcanic plumes in the atmosphere. Benefiting from developments favouring interactivity and flexibility, this platform thus aims to facilitate an in-depth assessment of the multi-scale impact of volcanic plumes on the atmosphere, from a local/regional to a global scale (Fig. 1). The atmospheric impacts of the gases and particles that constitute volcanic plumes are very diverse. These volcanic components modify the chemistry of the atmosphere and can also affect air traffic, air quality and, more broadly, the climate.

In addition, one part of the platform focuses on the restitution of gas and particle emissions from volcanic regions using remote sensing observations. Although the VOLCPLUME platform allows the study of any eruption in the world, target study areas are privileged (Antilles, Reunion, Iceland, Italy) because they host French volcanoes or volcanoes whose eruptions may affect the French or European atmosphere (Fig. 2). Knowledge of volcanic emissions, which are highly variable in time, is essential for initiating chemistry-transport modelling of volcanic plumes. It is also crucial for understanding the evolution of the activity of isolated or non-instrumented volcanoes, but also in the event of a strong eruption that can destroy the monitoring instruments deployed on the edifice or render them inoperative, as illustrated by the recent eruption of La Soufrière de Saint Vincent.

This platform is relevant not only to the atmospheric science community but also to the earth science community, in particular volcanologists and volcanological observatories.

Assessing the impact of a volcanic eruption on the atmosphere

Currently, the VOLCPLUME platform integrates satellite measurements of volcanic gases and particles from the Sentinel5P/TROPOMI and MetOp/IASI hyperspectral sensors as well as from the GOES, MSG and HIMAWARI geostationary satellite imagers. All of these observations make it possible to observe a volcanic plume, regardless of its geographical location on the globe. One of the original features of this platform is that it allows joint and interactive analysis of these satellite observations with data from networks of ground stations, such as the remote sensing measurements by solar and lunar photometry of the AERONET network (AErosol RObotic NETwork).

The platform also allows comparisons of the temporal evolution of the optical, microphysical and radiative properties of aerosols between several selected measurement stations (Fig. 3). As illustrated here with the eruptions of Etna at the end of February 2021, this type of analysis helps to assess the volcanic impact on the state of the European atmosphere.

Figure 1: Dispersion of the sulphur dioxide-rich volcanic plume from the eruption of La Soufrière volcano in St Vincent in April 2021, monitored by the Sentinel5P/TROPOMI satellite. The square symbols indicate the location of the photometric stations of the AERONET network whose observations are analysed in conjunction with the satellite observations on the platform. 
Figure 2: Monitoring of the explosive, ash-rich activity of La Soufrière volcano in Saint Vincent (West Indies) during its eruption in April 2021 using ABI observations from the geostationary GOES-16 satellite.

In the future, the VOLCPLUME platform will be able to integrate satellite observations from OMPS (Ozone Mapping and Profiler Suite), OMI (Ozone Monitoring Instrument), POLDER and CALIOP, as well as ground-based LIDAR observations and in-situ air quality monitoring measurements. Finally, it is also envisaged to host a modelling chain allowing the restitution of SO2 volcanic emissions at high temporal resolution by inverse modelling assimilating hyperspectral data from TROPOMI and IASI sensors.

AERIS/ICARE can quickly develop visualization interfaces

Because of its role as a data centre, the AERIS/ICARE unit has an infrastructure that is particularly conducive to the construction of tools for the joint exploitation of data from various sources. The centre is also demonstrating its ability to rapidly develop interactive visualisation interfaces for atmospheric monitoring applications. The software tools developed could be used to build other platforms for the study of extreme atmospheric events of another nature (natural or industrial risks), within the framework of continuous monitoring or for the study of seasonal phenomena, such as, for example, the resurgence of nitrate-rich aerosols associated with land-spreading activities. On-demand developments for specific scientific measurement campaigns or validation of satellite products can also be envisaged.

Analysis of the atmospheric impacts of the Etna plumes in the South of France by inter-comparison of one month time series of aerosol optical, microphysical and radiative properties (aerosol optical thickness, Angstrom coefficient, effective radius of fine or coarse modes, simple scattering albedo) restituted from photometric measurements at the Toulon (red) and Haute-Provence (blue) stations.