“Atlantification” of Greenland’s Fjords Increases Ice Loss and Threatens Local Ecosystems

Nature Communications, 10 December 2022

Warm Atlantic waters have been filling fjords and coastal areas along northeast Greenland for the past two decades, eroding the base of glaciers. This study consolidates one hundred years of oceanographic data to reveal that this region is shifting into an “Atlantification” hotspot. Within the past few decades, an influx of Atlantic water has flooded along Greenland’s coast, warming marine temperatures more than 1°C. These increased temperatures weaken the division between ocean layers, allowing Atlantic waters to flow closer to the surface. Fjords typically have piles of bedrock at their entrance (known as “sills”) that prevent lower ocean layers from flowing inland. Warm Atlantic waters can now flow over these sills and enter fjords, where they melt the base of glaciers and accelerate the loss of sea ice. These findings confirm that the Atlantification observed in the eastern Fram Strait and Barents Sea is now spreading to northeastern Greenland. Previously cold freshwater areas are now habitable to species such as Atlantic cod, beaked redfish, and deep-sea shrimp; such that the unique structure of Greenland’s marine environments is starting to resemble the Atlantic Ocean. Curbing global temperature rise to remain within the 1.5 °C limit of the Paris Agreement is crucial to maintaining Greenland Ice Sheet stability, and slowing these biodiversity changes in regions where Atlantic water threatens to restructure the local ecosystem.

https://www.nature.com/articles/s41467-022-35413-z