NASA announced on October 23, 2026, that altimetry satellites are tracking a strong El Niño event, comparing sea surface height anomalies against historical data from 1997 and 2015.
Satellite Altimetry Record
NASA’s Jet Propulsion Laboratory uses altimetry satellites to measure sea surface heights and track El Niño patterns. Josh Willis, project scientist for sea level missions at NASA’s JPL, noted that a 35-year record from nearly identical satellites flying similar ground tracks allows researchers to compare current conditions to past events.
Data from the TOPEX/Poseidon satellite, Jason-2, and the Sentinel-6 Michael Freilich satellite have contributed to tracking these sea surface height anomalies across the Pacific Ocean.
Comparing El Niño Events
According to NASA, sea levels are higher than normal across the central and eastern equatorial Pacific, closely resembling the conditions seen in October 1997. While the 2015-16 El Niño exhibited a different pattern where less warm water reached the South American coast, the 2026 event came on more suddenly and is on track to rival past heavyweights.
NOAA’s October 8, 2026 outlook indicated an 83 percent chance of a strong-to-very strong El Niño persisting through the first three months of 2027. Willis noted that while the current event looks like 1997, its exact winter impacts will depend on a chaotic atmosphere.
Key facts and where they come from
- A 35-year satellite altimetry record is being used to track the current El Niño event.
A 35-year satellite altimetry record lets scientists hold this year's El Niño up against its strongest predecessors.
- NOAA’s October 8, 2026 outlook called for an 83 percent chance of a strong-to-very strong El Niño.
NOAA’s El Niño outlook on October 8, 2026, called for an 83 percent chance of a strong-to-very strong El Niño through the first three months of 2027.
- Satellites used in the observations include TOPEX/Poseidon, Jason-2, and Sentinel-6 Michael Freilich.
Data are from the TOPEX/Poseidon satellite and the Sentinel-6 Michael Freilich satellite, respectively