As of June 2026, El Niño has officially arrived. Even during El Niño's early stages, satellites have observed characteristic changes along the equatorial Pacific, such as warmer-than-normal sea surface temperatures and higher-than-normal sea surface height. In June 2025 (left), conditions were neutral, while in June 2026 (right), El Niño was strengthening. Read More: NASAConcentrations of chlorophyll in the equatorial Pacific deviate from normal during El Niño events. These maps depict monthly average chlorophyll concentrations for June 2025 (left), under neutral conditions, and June 2026 (right), as El Niño was strengthening.