Extremely low chlorophyll concentrations in the oceans around Panama (blue = low, red = high) in February 2025, revealing the failure of the 2025 upwelling in the Gulf of Panama—for the first time in at least 40 years.

The natural phenomenon of upwelling, which occurs annually in the Gulf of Panama, failed for the first time on record in 2025. A study led by scientists from the Smithsonian Tropical Research Institute (STRI) indicates that the weakening of the trade winds was the cause of this event. This finding highlights the climate's impact on fundamental oceanic processes and the coastal communities that depend on them.

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.

Scientists from STRI have studied this phenomenon and their records show that this seasonal upwelling, which occurs from January to April, has been a consistent and predictable feature of the gulf for at least 40 years. 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.

In the recently published article in the journal PNAS, scientists suggest that a significant reduction in wind patterns was the cause of this unprecedented event, revealing how climate disruption can quickly alter fundamental oceanic processes that have sustained coastal fishing communities for thousands of years. Still, further research is needed to determine a more precise cause and its potential consequences for fisheries.

Upwelling events support highly productive fisheries and help protect coral reefs from thermal stress.

Chlorophyll concentrations in the oceans around Panama (blue = low, red = high) in February 2024, showing peak productivity in the Gulf of Panama during a period of typical upwelling.

The S/Y Eugen Seibold research vessel characterizes ocean and atmospheric conditions in the Pacific Ocean thanks to a collaboration between the Max Planck Institute for Chemistry and STRI.

Andrew Sellers taking samples during an expedition with the S/Y Eugen Seibold. The S/Y Eugen Seibold research vessel characterizes ocean and atmospheric conditions in the Pacific Ocean thanks to a collaboration between the Max Planck Institute for Chemist

This finding highlights the growing vulnerability of tropical upwelling systems, which, despite their enormous ecological and socioeconomic importance, remain poorly monitored. It also underscores the urgency of strengthening ocean-climate observation and prediction capabilities in the planet's tropical regions.

This result marks one of the first major outcomes of the collaboration between the S/Y Eugen Seibold research vessel from the Max Planck Institute and STRI.

More information: O'Dea, Aaron, Unprecedented suppression of Panama's Pacific upwelling in 2025, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2512056122. doi.org/10.1073/pnas.2512056122

Journal information: Proceedings of the National Academy of Sciences

Provided by Smithsonian Tropical Research Institute