The Role of Bering Strait in Regulating the Global Climate65.4N 169.9W
Alaska’s Bering Strait may play a critical role in the regulation of the global climate — including a knack for maintaining the Atlantic Ocean “conveyor belt” that bathes northern Europe in sultry currents and warm wet weather.
But squeeze shut the 53-mile-wide narrows between the Pacific and Arctic oceans off the western tip of Alaska — something that occurred during the last ice age when continental ice sheets locked up much of the world’s fresh water — and the oceanic engine that stabilizes the home planet’s climate becomes much more likely to go on the fritz and stay that way for a long time.
These resulting shutdowns have previously stalled the Gulf Stream and triggered abrupt swings between warmer and frigid climates, what scientists call Dansgaard-Oeschger and Heinrich events. These jarring shifts struck the North Atlantic as many as 25 times between 80,000 and about 11,000 years ago, all during moments when the Bering Land Bridge blocked all flow between Pacific and Arctic oceans.
The flow of the Gulf Stream and other elements of the global ocean circulation system deliver warm salty water to the North Atlantic, where it cools, grows denser, and sinks. At depth, this dense salty water starts flowing south. It then keeps rolling, eventually crawling into other hemispheres along a network of deep ocean currents that meander the globe over hundreds of years while equalizing the climate.
But introduce massive amounts of less dense fresh water into the mix, and the North Atlantic sinking starts to sputter, slowing the deep currents to the point where they temporarily die. The paradoxical result can be a chilldown of northern Europe and perhaps the entire northern hemisphere. Thus, smooth functioning of the Atlantic ocean “conveyor” becomes a “critical link” in keeping the world’s climate from making these wild swings (click here for more information).