We Are Unbelievably Screwed

A pre-peer review study has concluded that the Atlantic Meridional Overturning Circulation (AMOC) may already be in the early stages of an irreversible collapse.

If this happens, we could see temperature drops of 5-15° C in parts of Europe and devastating temperature increases in the south east United States, along with sea level rises well in excess of a meter.  (Probably enough to submerge Mar-a-Lago, but I'm looking on the bright side here.)

As Earth rapidly warms, fears over the collapse of a critical ocean current system are mounting. This event would wreak havoc on the global climate, and the latest research suggests this catastrophe may already be inevitable.

In a study that has yet to undergo peer review, researchers used a climate model to estimate how likely it is that the Atlantic Meridional Overturning Circulation, or AMOC, is “locked in” to collapse. Under conservative assumptions of Greenland ice sheet melt—a key driver of AMOC slowdown—they estimate a 10% chance that collapse is certain, rising to 80% by 2100 under the worst-case emissions scenario. The findings are currently available on the preprint server Earth ArXiv.

Stefan Rahmstorf, an oceanographer at the Potsdam Institute for Climate Impact Research in Germany who was not involved in the research, noted in an X post that the study is based on a single model. However, he said its conclusions are plausible based on overall knowledge of how fragile the AMOC currently is. Rahmstorf has studied this current system for more than 35 years.

………

If the AMOC shut down, it would trigger global climatic changes with catastrophic regional impacts. Sea levels would rise dramatically along the U.S. East Coast and other densely populated shorelines. There would also be major temperature shifts—in northern Europe, for example, the average temperature could drop by 9 to 27 degrees Fahrenheit (5 to 15 degrees Celsius). The world would see changes in extreme weather too, including more severe storms and a shift in the tropical rain belt, causing widespread drought in some areas and excessive rainfall and flooding in others.

And all of this can happen WITHOUT the collapse of the Thwaites Glacier in Antarctica.