The Beaufort Gyre is a wind-driven circular current in the western half of the Arctic Ocean, that alternates between a clockwise and counter-clockwise motion: when it circulates clockwise, it traps ice and melted freshwater, and when it spins counter-clockwise, it releases that freshwater and ice into the North Atlantic Ocean, southward past the east coast of Greenland. This trap-and-release cycle typically reverses every five to seven years, usually when a cyclonic storm in the North Atlantic moves into the Arctic, reversing the Gyre’s direction. However, the Gyre has been spinning in a clockwise direction for over twelve years, and scientists are concerned about what may happen when it eventually does reverse direction, releasing its accumulated hoard of fresh water into the North Atlantic.
"Nobody really understands what’s going on," says journalist Ed Struzik, "but it’s probably a combination of climate change and massive runoff of freshwater coming off the Greenland glacier that is preventing those big cyclones from forming over the North Atlantic and moving into the Arctic." Struzik is a fellow with the Institute for Energy and Environmental Policy at Queen’s University, and author of "Future Arctic: Field Notes from a World on the Edge."
And while the Beaufort Gyre continues its clockwise spin, it steadily accumulates a larger and larger concentration of fresh water. "Imagine all of the water that we have in the Great Lakes — that’s the amount of freshwater trapped in the Arctic just waiting to get out."
Aside from causing a significant cooling of the weather in Western Europe, the eventual release of such a large body of fresh water into the North Atlantic will be disruptive to ocean currents around the world: the warm surface water that flows northeast through the North Atlantic Current normally cools once it reaches the Arctic waters off of the northwest coast of Europe, causing it to sink into the depths to join a current that travels back south, to continue traveling along the large pattern of currents that circulate around the world. Fresh water, however, is more buoyant than saltwater, and can prevent the water from the northward current from sinking to rejoin the southward current, as is now happening with an increased amount of freshwater coming from Greenland’s melting glaciers — and a sudden release of the Beaufort Gyre’s freshwater stores would only serve to exacerbate the situation.
Struzik is also concerned about the apparent effect a warming Arctic has on the jet stream, causing it to dramatically loop north and south, bringing Arctic air farther south than usual, as has been the case in the record-breaking cold temperatures across North America in recent weeks.