Changes to the flow of the Labrador Current along the coast of Newfoundland and Labrador to Nova Scotia are leading to sudden warmings or drops in the oxygen levels of the waters in several regions including the St. Lawrence Gulf and Estuary. This change has dire consequences for marine ecosystems and fisheries. To better predict what could happen in the future, researchers from McGill University set out to answer the question: what controls the pathway of the Labrador Current?