Summer 2022 forest fires: an assessment of their impact on air quality

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Forest fires discharge significant amounts of fine particles into the atmosphere and the resultant plumes can travel vast distances. Using digital modelling, Ineris was able to simulate the dispersion and movement of particles emitted by the severe forest fires that occurred in France during the summer of 2022.

Smoke plumes from forest fires contain a variety of chemical compounds that can adversely affect air quality. They contain substantial amounts of fine particles including organic matter and black carbon. But fires also emit gases, such as carbon monoxide, and volatile organic compounds.
The vast quantities of pollutants discharged during the massive fires in summer 2022 had a marked effect on air quality—in some cases at distances of several hundred kilometres.
Using digital modelling, it is possible to simulate the dispersion and movement of these plumes. Detecting serious fires relies on satellite data obtained and processed in near-real time. This is then used to estimate the amount of emissions after cross checking the characteristics of burnt areas. This information is then fed into a chemical transport model that simulates the dynamics of the plume and the chemical processes that can take place while factoring in changes in numerous meteorological parameters, such as wind and temperature. The exact quantity of emitted pollutants remains highly difficult to determine, and the modelled surface particle concentrations require comparison with observations on the ground. However, changes in the shape of the plumes and their behaviour over time have been closely corroborated by satellite observations.
The animation presented for the mid-July to mid-August 2022 period shows the dispersion of particles resulting from the major forest fires that occurred in France. It of course demonstrates the contribution of the Gironde department fires in Landiras and La Teste-de-Buch, but also those in the Monts d'Arrée, the Hérault department, and others.


The digital simulations are based on the CHIMERE model co-developed by Ineris and the CNRS and implemented for the French Prev'air national air quality forecasting platform operated by Ineris on behalf of the French Ministry of Ecological Transition and Regional Cohesion , in partnership with Météo-France, the CNRS (LMD/IPSL), and the Central Laboratory for Monitoring Air Quality.
Fire plume dispersion calculations are based on same-day forecasts made during the summer. Given the exceptional nature of these fires, the simulations are not corrected by merging or assimilating data from the field as is usually the case with Prev'air solutions. Information on emissions from forest fires comes from the Copernicus Atmosphere Monitoring Service (CAMS), which provides comprehensive information on air quality. Daily forecasts are made for Europe by a unit jointly coordinated by Météo-France and Ineris. Ineris also coordinates the CAMS decision support unit, which provides interpretive support for air quality incidents and trends.