Dakar Niños reduced biological production off northwest Africa via changes in winds and coastal waves

Why does biological production in the coastal upwelling region off Senegal and Mauritania vary so strongly from year to year? A study has examined the period 2003–2023 and identified years with unusually low or high production during the main upwelling season from March to May, including six previously undescribed low-productivity years. These events mostly coincided with exceptionally warm surface conditions off the coast, known as Dakar Niños. Using satellite observations, processed weather and ocean data, and model simulations, the study showed that productivity is controlled not only by local winds but also by coastal trapped waves, which propagate from the equatorial Atlantic along the coast of the Gulf of Guinea, altering nutrient availability. The results advance our understanding of the physical mechanisms governing one of the world's most important coastal upwelling systems and provide a key foundation for predicting future ecological changes.

Original paper

https://www.nature.com/articles/s41598-025-31860-y