En France, l’ozone est le seul polluant atmosphérique dont les teneurs moyennes annuelles ont augmenté au cours des deux dernières décennies. Ce constat est d'autant plus préoccupant que les niveaux de concentrations mesurés sont suffisants pour affecter la santé, la végétation et le rendement des cultures. L’ozone résulte de réactions complexes entre des polluants déjà présents dans l’atmosphère sous l’action des rayonnements ultraviolets. La réduction des rejets de ces polluants, résultat des stratégies et plans d’action mis en œuvre depuis plusieurs années, a toutefois permis de diminuer l’intensité des pics d’ozone sur une partie du territoire malgré des conditions météorologiques peu favorables.
Ozone pollution: still a worrying situation despite progress
In France, ozone is the only atmospheric pollutant whose average annual levels have increased over the last two decades. This observation is all the more worrying as the concentration levels measured are sufficient to affect health, vegetation and crop yields. Ozone forms as a result of complex reactions between pollutants already present in the atmosphere due to the action of ultraviolet radiations. The reduction in the releases of these pollutants, as a result of strategies and action plans implemented for several years, has nonetheless made it possible to reduce the intensity of ozone peaks in some regions despite unfavourable weather conditions. The significant impact of climate change and long-range transport of air pollution regarding ozone levels, highlighted by various studies, confirms the need at European and international levels to continue and strengthen actions to reduce emissions of pollutants that cause ozone.
In France, ozone is the only atmospheric pollutant whose average annual levels have increased over the last two decades. This observation is all the more worrying as the concentration levels measured are sufficient to affect health, vegetation and crop yields. Ozone forms as a result of complex reactions between pollutants already present in the atmosphere due to the action of ultraviolet radiations. The reduction in the releases of these pollutants, as a result of strategies and action plans implemented for several years, has nonetheless made it possible to reduce the intensity of ozone peaks in some regions despite unfavourable weather conditions. The significant impact of climate change and long-range transport of air pollution regarding ozone levels, highlighted by various studies, confirms the need at European and international levels to continue and strengthen actions to reduce emissions of pollutants that cause ozone.
L'ozone à ne pas confondre avec la couche d'ozone
Découvrez le processus de formation du gaz irritant polluant néfaste pour la santé.
Données
Données relatives à la publication
- Données des graphiques 1 et 2, Geod'air, données de juillet 2021
- Données du graphique 3, étude APollO, mai 2019
Méthodologie
Analyses des données de concentrations en ozone dans l'air extérieur : méthodologie et résultats détaillés.