Greenland is Dumping Freshwater into the North Atlantic...and its Implications

In a new study lead by Jonathan Bamber, scientists found that, over the past few decades, the melting of Greenland glaciers has been feeding an anomalous spike in North Atlantic freshwater. If it continues as it has been, in the coming years the spike will rival the effects of the Great Salinity Anomaly—a bulge of fresh water that can affect the circulation patterns of the whole Atlantic Ocean.

Here’s the background: In the late 1960s, the first Great Salinity Anomaly (GSA) formed off the eastern shores of Greenland. Formed by a spike in Arctic ice melt, the event led to the formation of a thin sheet of fresh water that floated on the typically cold, salty waters of the north Atlantic Ocean. Over the subsequent years, the anomaly drifted about the North Atlantic, first around the southern tip of Greenland, then off to the coast of Canada, then up and around, along the Gulf Stream to northern Europe. As it traveled, the freshwater pool acted as a cap, limiting the interaction between the air and the ocean.

According to Oceanus, the magazine of the Woods Hole Oceanographic Institution, “[t]he GSA acted as a sort of moving blanket, insulating different parts of the deep ocean from contact with the atmosphere as it moved around the gyre.” Similar events have happened in the decades that followed, and scientists have found that they can cause unusual temperature patterns for the United States and northern Europe, and may even affect fish populations.

Paper link.