August 27, 2026 — As the 2026 El Niño strengthens in the equatorial Pacific, satellites are capturing the first major signs of disruption to the marine food web.
According to by NASA’s Earth Observatory observations, satellite measurements show a substantial drop in surface concentrations of chlorophyll across the Central Pacific compared with neutral conditions in June 2025. Chlorophyll is the pigment that helps plants absorbs sunlight to generate energy, and its reduction indicates a decline in phytoplankton, the base of the ocean’s food webs.
Hyung-Gyu Lim, an associate professor of oceanography at Chonnam National University in South Korea, told Mongabay by email that a developing El Niño can slow the process of upwelling, where nutrient-rich cold waters rise from the ocean depths to the surface. “This may trigger less nutrient supply. It is not surprising for me,” Lim said.