When people think about the risks of climate change, the idea of abrupt changes is pretty scary. Movies like “The Day After Tomorrow” feed that fear, with visions of unimaginable storms and populations fleeing to escape rapidly changing temperatures.
While Hollywood clearly takes liberties with the speed and magnitude of disasters, several recent studies have raised real-world alarms that a crucial ocean current that circulates heat to northern countries might shut down this century, with potentially disastrous consequences.
That scenario has happened in the past, most recently more than 16,000 years ago. However, it relies on Greenland shedding a lot of ice into the ocean.
Our new research, published in the journal Science, suggests that while Greenland is indeed losing huge and worrisome volumes of ice right now, that might not continue for long enough to shut down the current on its own. A closer look at evidence from the past shows why.
Blood and water
The Atlantic current system distributes heat and nutrients on a global scale, much like the human circulatory system distributes heat and nutrients around the body.
Warm water from the tropics circulates northward along the U.S. Atlantic coast before crossing the Atlantic. As some of the warm water evaporates and the surface water cools, it becomes saltier and denser. Denser water sinks, and this colder, denser water circulates back south at depth. The variations in heat and salinity fuel the pumping heart of the system.
If the Atlantic circulation system weakened, it could lead to a world of climate chaos.
When people think about the risks of climate change, the idea of abrupt changes is pretty scary. Movies like “The Day After Tomorrow” feed that fear, with visions of unimaginable storms and populations fleeing to escape rapidly changing temperatures.
While Hollywood clearly takes liberties with the speed and magnitude of disasters, several recent studies have raised real-world alarms that a crucial ocean current that circulates heat to northern countries might shut down this century, with potentially disastrous consequences.
That scenario has happened in the past, most recently more than 16,000 years ago. However, it relies on Greenland shedding a lot of ice into the ocean.
Our new research, published in the journal Science, suggests that while Greenland is indeed losing huge and worrisome volumes of ice right now, that might not continue for long enough to shut down the current on its own. A closer look at evidence from the past shows why.
Cows in California are dying at much higher rates from bird flu than in other affected states, industry and veterinary experts said, and some carcasses have been left
Residents of Florida's Gulf Coast are digging out from mountains of sand after Hurricanes Helene and Milton clobbered them with back-to-back hits in less than two weeks
It takes water to flush a toilet yet tens of thousands of North Carolinians have been without it since Hurricane Helene ripped through the state three weeks ago