How does summer upwelling affect the Somali and Arabian coasts?

During the summer months, the southwest monsoon winds drive a pronounced upwelling of deeper, colder waters along the Somali and Arabian coasts. This seasonal phenomenon significantly impacts the marine environment by replacing warmer surface waters with much cooler water, which can reach temperatures as low as 57 °F (14 °C).12

This process is ecologically vital because upwelling brings nutrient-rich water toward the surface. These nutrients support the rapid reproduction of phytoplankton, which in turn fuels the growth of zooplankton and provides an abundant food supply for larger marine life. Consequently, these regions become some of the most biologically productive areas in the ocean, supporting rich fisheries that are essential to the local marine ecosystem.34

The intensity of this upwelling is closely tied to the monsoon regime, which also dictates the flow of the Somali Current and the Monsoon Current in the northern Indian Ocean.142