Freshwater pool of the 2026 El Niño

As the Pacific Ocean moves into an El Niño phase, scientists are monitoring changes in sea-surface temperature, but also sea-surface salinity – which is another key indicator of this phenomenon. Measurements from satellites such as the European Space Agency's SMOS mission are revealing how freshwater and salt patterns shift across the Pacific as this year’s El Niño develops – offering a potential new pathway for early detection.

Drawing on data from ESA’s SMOS and NASA’s SMAP missions and other data sources, the image shows the position of the freshwater pool as of June 2026.

See full animation: Shifting freshwater pool of the El Niño–Southern Oscillation

Read full story: SMOS salinity could offer early indicator of El Niño