The Rise of the Arctic Ocean as a Bedrock of our Climate System: A Long Journey from the Arctic to Antarctica Using a Proximity Surface Temperature Measurement

So much on this planet depends on a simple matter of density. In the Atlantic Ocean a conveyor belt of warm water heads north from the tropics to the bottom of the sea. That makes it denser, so it sinks and heads back south, finishing the loop. The AMOC moves fifteen million cubic meters of water per second.

Nicholas Foual, an assistant scientist who was not involved in the study, said that the AMOC is a bedrock of our climate system. It’s something that we take for granted, it redistributes heat globally.

That’s a tipping point that would come much sooner than anyone thought. She says they got scared by their results and that’s why they did a paper about it. “We checked and checked and checked and checked, and I do believe that they’re right. Of course, we could be wrong and I hope that is not the case. There is a lot of debate in the scientific community over how to handle the decline of the AMOC.

It’s abundantly clear to researchers that the Arctic is warming up to four and a half times faster than the rest of the planet. The oceanographer Marlos Goes from the University of Miami and the Atlantic Oceanographic and Meteorological Laboratory were not involved with the new paper. As the ice sheet declines, freshwater is injecting into the sea. That deluge of freshwater is less dense than saltwater, meaning less water sinks and less power goes into the AMOC conveyor belt.

The AMOC calculations were done by Ditlevsen using the Atlantic sea surface temperatures as a proxy. These readings go all the way back to the 1870s, thanks to measurements taken by ship crews. Researchers could compare the temperatures before and after fossil fuel burning in order to understand changes to the climate.

Peter Ditlevsen is a professor of ClimatePhysics at the University of Copenhagen and an author of the study. “It calls for quite immediate actions. We need to cut emissions. We need more brakes on the train.”

Why it’s so important to figure out when the Atlantic Ocean current might be very cold: Why it might affect agriculture, climate change, and mass migration

Europe has a lot to thank the AMOC for. Cities like London and Paris are hotter than those in North America.

“In Scandinavia, we have a sort of pleasant, mild climate,” Ditlevsen says. “And if you compare that with the U.S., we are at the latitude of Alaska, which is much colder than Scandinavia.”

The water is denser and heavier due to the cold. The ocean current is like a conveyor belt that flows in the direction it came from along the ocean floor.

While researchers disagree on the timing of such a collapse, there is broad consensus on the potential consequences. A collapse in the AMOC could have ripple effects around the planet. Climate change is already happening and could get worse if temperatures in Europe and the tropics don’t fall.

Rainfall could decrease across the Sahel region of Africa, threatening crop production for millions of people. Sea levels could rise faster in the Eastern U.S., even as the monsoon weakens across Asia.

“It is going to affect agriculture,” he says. “It’s going to affect disease, especially in the equatorial region. mass migration will be affected by it.

Source: https://www.npr.org/2023/07/27/1190519762/why-its-so-important-to-figure-out-when-a-vital-atlantic-ocean-current-might-col

Foukal’s study of the Arctic melts, melting ice and the collapse of the Atmosphere is critical to the determination of the time to collapse

Foukal says this most recent study relies on temperature records from a small part of the system and doesn’t simulate what would happen to the entire current itself. He says it’s also crucial to understand the cause of a collapse to estimate the timing — something Ditlevsen’s study didn’t address.

A similar situation could happen again, as humans continue to burn fossil fuels. Ice in the Arctic and Greenland’s ice sheets are melting at an increasing pace, also adding fresh water to the Atlantic. But Foukal says researchers are still trying to determine whether that would be enough to cause a complete collapse.