L'océan Arctique a franchi un point de basculement en raison de la chute des niveaux de nitrates

28 mai 2026

Rapporté par l'IA

L'océan Arctique a franchi un point de basculement aux alentours de 2009, selon une nouvelle étude montrant que la perte de banquise a considérablement réduit les niveaux de nitrates dans l'eau.

Des chercheurs de l'Université d'Édimbourg ont analysé plus de 20 ans de données provenant du détroit de Fram. Ils ont découvert que le déclin des nitrates a commencé lorsque la banquise a reculé rapidement, exposant les eaux peu profondes à davantage de lumière solaire et accélérant un processus appelé dénitrification benthique qui élimine ce nutriment de l'eau de mer.

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vendredi 05 juin 2026 06h24