Study: Expected Ocean Current Shutdown Imperils World

An ocean current network that controls temperatures around the world could collapse as soon as 2025. Its collapse could affect “every person on the planet,” a new study says. 

The system is called the Atlantic Meridional Overturning Current (AMOC). The melting of polar and Greenland ice is dumping freshwater into the AMOC. The AMOC is a saltwater system. The freshwater threatens to shut the AMOC down. If that happened, it could trigger several outcomes. Europe could be sent into an ice age. Sea levels on the East Coast of the US could rise. Finally, rainfall patterns across the planet could be impacted. That could cause a disaster.

“I think we should be very worried,” the study leader told The Guardian. The study used sea surface temperatures dating to 1870 to create an AMOC shutdown model. It was published Tuesday.

The AMOC system includes the Gulf Stream. It helps balance weather across the planet. One of the things the AMOC does is send warmer water to Europe. Without it, the continent would be colder. The AMOC collapsed between 115,000 and 12,000 years ago. That led to multiple ice ages. 

A modern AMOC shutdown was dramatized in a 2004 disaster movie called The Day After Tomorrow. In it, climate change led to an AMOC shutdown. In the movie, the collapse led to an ice age right away. Scientists said that was too fast. They did say that global warming, though, could create an ice age. 

Even scientists who aren't sure about this study’s findings take it seriously. Its forecast of an AMOC shutdown between 2025-2095 with “95% confidence” goes against a 2019 United Nations report. That report said such an event won't likely occur this century.

Reflect: Do you think changes in the ocean currents could affect the weather and environment where you live? Explain.