Science Snippets: Studies Warn "Day After Tomorrow" Ocean Current is in Trouble

Draft script:

The Day After Tomorrow was a blockbuster film released in 2004. I didn’t watch it, although I did have an Opinion article about it published in the local, daily newspaper in Tucson, Arizona. The film is back in the news with an article published by USA Today. Published on 23 April 2026, the article at USA Today is titled 2 studies warn “Day After Tomorrow” ocean current is in trouble. It points to two peer-reviewed papers, as introduced in the subhead: “A pair of studies bring bad news for the ocean current at the center of the fictional (and scientifically inaccurate) ‘Day After Tomorrow’ climate change disaster movie.”

Here’s the lede: “The potential collapse of a key Atlantic ocean current -- due to human-caused climate change – is in the news again.”

The following two paragraphs provide a decent overview: “You’d be hard-pressed to come up with a scarier scenario than what’s going on now with the Atlantic Meridional Overturning Circulation, or AMOC, the fickle Atlantic ocean current whose weakening and eventual collapse could change the climate and weather for hundreds of millions of people.

A pair of new scientific studies detail the present and potential future of the AMOC, which was the ocean current at the center of the fictional (and scientifically inaccurate) ‘Day After Tomorrow’ climate change disaster movie in 2004.” Pointing out that the film is scientifically inaccurate is unnecessary. As with most movies rooted in fiction, The Day After Tomorrow occasionally takes liberty with facts. It doesn’t claim to be a documentary film. It promises only action and adventure. Based on the money it earned, it delivered.

A subsection titled “What is the AMOC?” includes four critical paragraphs: “The AMOC is a crucial conveyor belt for ocean water and air, which influences weather. Warm, salty water moves north from the tropics along the Gulf Stream off the U.S. East Coast to the North Atlantic, where it cools, sinks and heads south. The faster it moves, the more water is turned over from warm surface to cool depths. The cycle keeps northern Europe several degrees warmer than it would otherwise be and brings colder water to the coast of North America. Previous studies in 2018 and 2021 have also found that a collapse of the AMOC is possible at some point this century.”

Beneath the subtitle “Study says AMOC is weakening,” we find two peer-reviewed, open-access papers in the renowned Science Advances. Links to both papers are embedded in the USA Today article: “The April 8 study by scientists from the University of Miami, published in the peer-reviewed journal Science Advances, revealed that over the past 20 years, the AMOC is weakening at four different latitudes

throughout the western boundary of the North Atlantic Ocean.”

One of the co-authors of this peer-reviewed article is then quoted: “In a sense, observations at the western boundary, in isolation from the eastern boundary,

constitute the canary in a coal mine for the tendency of the AMOC. These findings support the evidence of a broader weakening of the AMOC.”

The article continues with an embedded link to the second peer-reviewed, open-access paper: “Meanwhile, an April 16 study by European scientists, also in the journal Science Advances, found that “most climate models underestimate its decline. The AMOC is on course to slow by more than 50% by the end of the century, a ‘substantial weakening’ that’s 60% stronger than that estimated by the average of all climate models, according to the study.”

The following subsection is titled “How close to a ‘tipping point’ is the AMOC?” It quotes the same co-author of the April 8 study: “the AMOC is likely going towards a tipping point, which means it enters a very weak state from which it could not recover without great effort. If the weakening currently observed continues at the same rate, a collapse of the AMOC could be reached in about 140 years. However, this weakening could accelerate and occur earlier, underscoring the importance of continued monitoring of the AMOC.”

I now turn, briefly, to the two peer-reviewed, open-access papers in Science Advances. The first, published on 8 April 2026, is titled Meridionally consistent decline in the observed western boundary contribution to the Atlantic Meridional Overturning Circulation. Authored by six scholars, the Abstract tells the tale: “Despite numerous model-based analyses indicating a notable decline in the Atlantic Meridional Overturning Circulation (AMOC) in recent decades, robust, long-term evidence from multilatitudinal in situ observations remain limited. This study uses observational data from four mooring arrays, positioned along the western boundary of the North Atlantic (from 16.5°N to 42.5°N), to examine trends in the deep western overturning transports, derived from the cross-slope gradient in ocean bottom pressure or its equivalent, below and relative to 1000 meters that are linked to changing conditions at the western boundary. We identify a meridionally consistent decline in deep western overturning transport across these latitudes over the past two decades. This decline, observed at the western boundary, may serve as an effective indicator of AMOC weakening, despite the partial compensatory effect of overturn strengthening at the eastern boundary.”

In other words, the AMOC hovers on the brink. It is already declining. The peer-reviewed paper indicating it “is already in decline and could be at or near a

critical tipping point” is cause for concern. Yet again, the scientifically conservative approach abandons the precautionary principle, thereby threatening the extinction of our species.

The second paper published in Science Advances was published on 15 April 2026 and titled Observational constraints project a ~50% AMOC weakening by the end of this century. Created by four scholars, the paper focuses on the AMOC. Its findings, reported in the Abstract, are consistent with those of the previous paper: “Climate models show considerable discrepancies in their future projections around the Atlantic, mainly due to uncertainties in the fate of the … AMOC. Climate models suggest a reduction in AMOC strength of 32 ± 37% by 2100 ... To refine this estimate and reduce its uncertainty, we use four different observational constraint methods. The best one, which provides the lowest leave-one-out error, integrates a large set of observable variables using ridge-regularized linear regression—a method unusual in climate science. It gives an estimate of the AMOC slowdown of 51 ± 8% (90% probability), i.e., a weakening ∼ 60% stronger than suggested by the multimodel mean. This refinement mainly results from correcting a bias in South Atlantic surface salinity, consistent with recent studies emphasizing its role in the proximity to an AMOC tipping point. This more substantial AMOC weakening has key implications for future adaptation strategies.”

Yes, that’s bad news. The AMOC is weakening now, and it poses a significant problem in the very near future.