Each year, during Central America’s dry season (usually between December and April), strong northerly trade winds drive important oceanic processes in the Gulf of Panama. These winds push surface water, causing cold, nutrient-rich water from deep to rise toward the surface.
This process, known as upwelling, plays a major role in the region’s marine life. This promotes productive fisheries, protects coral reefs from heat stress, and helps keep waters along Panama’s Pacific beaches cool during the busy “summer” holiday season.
A 40-year pattern suddenly changed.
Scientists at the Smithsonian Tropical Research Institute (STRI) have been tracking this seasonal upwelling for decades. Their records show that from January to April, this phenomenon has been a reliable and predictable part of the Gulf of Panama for at least 40 years.
But in 2025, researchers documented something they had never seen before. For the first time, their records show that this important oceanographic process did not occur. Normal seasonal cooling has weakened, and the expected increase in ocean productivity has also diminished.
This may be due to the weak wind.
In an article recently published in a magazine PNASscientists suggest that a significant drop in wind patterns likely caused the unprecedented failure. The discovery shows how rapidly climate change is impacting fundamental ocean processes that have supported coastal fishermen for millennia.
Researchers warn that more research is needed to determine the exact cause and understand what this event means for fisheries.
Tropical oceans need better monitoring
This finding indicates the increasing vulnerability of tropical upwelling systems. These systems are critical to ecosystems and coastal economies, but they remain poorly monitored in many parts of the world.
The findings also highlight the need to improve ocean climate observations and predictions across the tropics.
This result is one of the first major results of the collaboration between the Max Planck Institute’s S/Y Eugen Seibold research vessel and STRI.
