Les incendies dans l'Arctique libèrent du carbone stocké depuis des millénaires

13 mai 2026

Rapporté par l'IA

Les incendies qui font rage dans les régions arctiques et boréales consument du carbone ancien contenu dans les sols, libérant ainsi beaucoup plus de dioxyde de carbone que ce que prévoyaient les modèles climatiques. Une nouvelle étude de carottes de sol montre que certains feux brûlent de la matière organique vieille de 5 000 ans.

Meri Ruppel, de l'Institut météorologique finlandais, a dirigé ces recherches. Son équipe a collecté des carottes de sol sur des sites incendiés et a découvert que la végétation de surface déclenche souvent une combustion lente dans les couches plus profondes et plus anciennes. Ce processus libère du dioxyde de carbone ainsi que du carbone noir, qui absorbe la lumière du soleil et accélère la fonte des glaces lorsqu'il se dépose sur la glace ou la neige.

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