Deoxygenation and Acidification in the St. Lawrence Estuary
Highlights
Oxygen levels in the deep waters of the St. Lawrence estuary have been monitored since the early 1970s. In 2022, they reached their lowest values ever recorded and remained close to these record lows in 2023 and 2024. Annual pH measurements carried out since 2014 reveal a trend towards acidification of the estuary’s deep waters, characterized by a drop in pH, which reached a record low in 2023.