For the first time since records began 40 years ago, the cold, nutrient-rich waters of the Gulf of Panama failed to emerge this year.
Upwelling events support highly productive fisheries and help protect coral reefs from thermal stress.

Scientists have spotted something dramatically unusual in the ocean, and it could be a warning sign of things to come.

Warm air dances with cold air; cold water chases warm water. It's all a part of a predictable, stable dance of currents and climate patterns that naturally happen all across the Earth. Until it doesn't.

For the first time since records began 40 years ago, the cold, nutrient-rich waters of the Gulf of Panama failed to emerge this year. Scientists aren't sure if it's a fluke or a new normal.

Specifically, the Gulf of Panama’s seasonal upwelling system has consistently delivered cool, nutrient-rich waters via northerly trade winds every January-April for at least 40 years. But not this year.

"Time will tell if this is a real-life example of a climate tipping point – if the failure of upwelling continues in future years," said Tim Lenton, of the University of Exeter in the United Kingdom, a tipping point expert who was not involved in the new research.

The findings were reported last week in the peer-reviewed journal Proceedings of the National Academy of Sciences.

What are 'tipping points'?

Scientists have long feared that some major features of the Earth's climate could dramatically come undone if human-caused climate change continues. It's the premise behind the science fiction movie "The Day After Tomorrow," which is (very) loosely based on a real concern that a major ocean current could relatively rapidly collapse in a warming world.

Researchers have chronicled a host of similar climate change tipping points. While the Gulf of Panama isn't one of those tipping points, it does bring concerns about coral reefs that are a part of the conversation.

"Whether it is a tipping point or not, it is bad news for a different tipping point that is underway – the loss of coral reefs, linked to extreme warmth of tropical sea surface temperatures – as much needed cooling from the upwelling has not happened this year," Lenton said.

"The change could also trigger tipping points in the open ocean ecosystem and associated fisheries as there will be much less primary production this year."

What is upwelling?

According to the Smithsonian Institution's Tropical Research Institute, which led the study, during the dry season in Central America (generally between December and April), northern trade winds generate upwelling events in the ocean waters of the Gulf of Panama.

Upwelling is a process that allows cold, nutrient-rich waters from the depths of the ocean to rise to the surface. This dynamic supports highly productive fisheries and helps protect coral reefs from thermal stress. Thanks to this movement of water, the sea along Panama’s Pacific beaches remains cooler during the "summer" vacation season.

However, researchers recently recorded that in 2025, this vital oceanographic process did not occur for the first time. As a result, the typical drops in temperature and spikes in productivity during this time of year were diminished.

Further research is needed

What are the likely causes of this upwelling suppression? "The prime suspect is a reduction in winds," said Aaron O'Dea, the Smithsonian's lead scientist on the project. "Upwelling typically occurs every year when the trade winds blow over the Isthmus. That didn't happen as frequently or as strongly as normal years, so it makes sense."

"The more important question is, why did the winds not blow? We currently do not know why and deciphering this will take a little more time," he told USA TODAY.

It's not clear if human-caused climate change played a part in the upwelling suppression this year.

Regardless, this study reveals how climate disruption can quickly alter fundamental oceanic processes that have sustained coastal fishing communities for thousands of years, according to the Smithsonian Institution. Still, further research is needed to determine a more precise cause and its potential consequences for fisheries.

What's next?

According to O'Dea, "We're monitoring it daily through various means including satellite and direct measurements. We also have a cruise planned to sample the subsurface waters early next year to see if the same thing happens or not."

"To better understand what happened and why, and predict if it will happen again, we have gathered a team of collaborators from the Smithsonian and the Max Planck Institute to analyze atmospheric and ocean data together more rigorously and apply high-resolution modelling approaches for future predictions."

"One of my hopes for this paper was that it spurs interest and directed research into this and events like this in tropical waters that have always been assumed to be reliable but which in fact, may no longer be so reliable. I think we have now ignited that interest and the next, and more challenging task, will be to sift through data and figure out the details. At least we have started!" O'Dea told USA TODAY.

This article originally appeared on USA TODAY: A steady ocean pattern just failed for the first time ever observed

Reporting by Doyle Rice, USA TODAY / USA TODAY

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