A New Idea to Save the Climate? Dam the Bering Strait. (New York Times)
A satellite view of the Bering Strait, which separates northeastern Russia and Alaska, in summer. Credit...NASA
Excerpt:
Brightening clouds. Refreezing the Arctic. Floating a giant parasol in outer space. To the ranks of out-there ideas for countering climate change, two Dutch scientists have added this: building a 50-mile-long dam across the Bering Strait, the shallow waterway that separates Russia and Alaska.
In a study published on Friday in the journal Science Advances, the researchers show that, under certain conditions, such a dam could prevent a collapse of a network of ocean currents, known as the AMOC, that plays a central role in regulating Earth’s climate.
The AMOC (pronounced AY-mock) has weakened in recent decades, and a growing body of evidence suggests human-caused warming could someday cause it to shut down or slow significantly, with grave effects on the weather on multiple continents.
The new study is a “proof of concept,” not an action plan, one of its authors, Jelle Soons, a doctoral candidate at Utrecht University in the Netherlands, said. More research is needed to confirm that such a dam would work as intended and to assess its feasibility and environmental side effects, Mr. Soons said.
Still, he said, humanity could someday be forced to take drastic measures to avert the worst effects of global warming. While cutting carbon emissions is still the best way to prevent an AMOC collapse, his findings show that “in a worst-case scenario,” a Bering Strait dam could be an option, Mr. Soons said.
The AMOC, or Atlantic Meridional Overturning Circulation, is part of a giant loop of water that snakes through the world’s oceans. It carries warm, salty water from the tropical Atlantic up past the Eastern Seaboard and toward Europe. There, the water releases its heat into the air and helps moderate the weather in Britain and the Nordic countries. In the process, the water cools, sinks and heads back south, where it goes on to influence rainfall patterns in Africa, South America and beyond.
Now, though, warming from greenhouse gases in the atmosphere is disrupting this vast oceanic conveyor belt. As temperatures rise, the Arctic gets rainier and Greenland’s ice sheet melts, more fresh water is pouring into the North Atlantic, making its surface less salty. That prevents the water of the AMOC from sinking at the loop’s northern end, which in turn causes it to draw less warm water northward from the tropics.
Should the belt stop turning altogether, Northern Europe would grow colder, deprived of the warmth the AMOC brings. With less water moving north through the Atlantic, more of it would slosh toward the U.S. East Coast, raising sea levels there. Tropical rainfall patterns would be rearranged, parching some areas while dousing others
