A recent international study has uncovered a rare and alarming disruption of the tropical upwelling system in the Gulf of Panama, revealing just how vulnerable warm-water marine environments may be to climate-related changes. The research team, which includes scientists from the Smithsonian Tropical Research Institute, the Max Planck Institute for Chemistry and multiple global partners, warns that the collapse of this natural process triggered rapid and widespread ecological damage.
Fisheries Shrink as Plankton Levels Plummet
The sudden disappearance of upwelling normally responsible for bringing cool, nutrient-rich water to the surface caused an immediate breakdown in the food web. Phytoplankton, the microscopic plants that form the foundation of marine life, declined sharply. With the base of the food chain disrupted, fish species that depend on plankton, such as sardines, mackerel and cephalopods, experienced significant population drops in coastal areas.
This decline has already affected fisheries that support both commercial industries and local communities. For many coastal households, these species provide essential protein sources and livelihoods. Scientists say that even short-term interruptions in upwelling can lead to long-term economic and nutritional consequences.
Coral Reefs Hit by Prolonged Heat Stress
Coral reefs in the region also suffered as the absence of deep, cool water removed a natural buffer against rising sea temperatures. Without this seasonal cooling effect, reefs endured extended thermal exposure, making bleaching events in early 2025 more severe and widespread.
Dissolved oxygen levels in the water column dropped as well, placing additional pressure on bottom-dwelling and deep-sea species. These combined stressors highlight how closely tropical marine systems depend on predictable ocean circulation for survival.
A Visual Reminder of Fragile Ecosystems
Coral reefs near the San Blas Islands in Panama offer a stark example of what is at stake. The vibrant ecosystems that support fish, corals and countless marine species are increasingly threatened by warming oceans and the loss of natural cooling cycles.
Monitoring Gaps Leave Tropical Regions at Risk
One of the most important lessons from this event is how easily it could have gone unnoticed. While temperate upwelling systems are monitored extensively, tropical regions like the Gulf of Panama lack robust observational infrastructure. This monitoring gap means scientists often detect problems only after ecological damage has already begun.
Despite the critical role upwelling plays in carbon cycling, fisheries productivity and climate regulation, tropical data is still underrepresented in global climate models. Researchers caution that if disruptions like this continue or begin affecting other regions of the Eastern Tropical Pacific the impacts could unfold more rapidly and with far less warning than previously expected.
Call for Stronger Monitoring and Better Climate Models
The study’s authors emphasise the urgent need to expand ocean monitoring networks and to improve modelling of wind–ocean interactions, especially in tropical zones. They stress that integrating more tropical data into global systems will be essential for predicting climate impacts and protecting marine biodiversity.
As the world continues to warm, the stability of entire marine ecosystems may depend on recognising these early warning signs and acting before temporary disruptions turn into long-term ecological shifts.