NASA Satellites Analyze the 2026 El Niño Event

Tracking El Niño from Space

Scientists are using a 35-year record of satellite altimetry to analyze the 2026 El Niño event by comparing it to historical occurrences, specifically the powerful patterns of 1997-98 and 2015-16. El Niño is a climate cycle occurring every two to seven years where trade winds weaken, allowing warm equatorial Pacific water to shift eastward.

How Altimetry Works

Altimetry satellites measure sea surface height, which serves as a proxy for heat accumulation. Because water expands as it warms, higher sea levels indicate the buildup of heat associated with El Niño.

• Comparison: While the 2026 event emerged more suddenly than the 1997-98 event, current data shows similar characteristics, such as the tilt of sea levels and high water extending to South America.
• The 2015-16 Distinction: The 2015-16 El Niño differed, as warm water did not push against South America as strongly, leading to different regional rainfall impacts.

Scientific Uncertainty

Josh Willis, a project scientist at NASA’s Jet Propulsion Laboratory, notes that while the current event shows strong potential, predicting exact impacts remains difficult. El Niño signals interact with a chaotic atmosphere, meaning that historical similarities do not guarantee identical outcomes.

According to an October 8, 2026, NOAA outlook, there was an 83 percent chance of a strong-to-very strong El Niño persisting through early 2027. Researchers emphasize that while satellites provide high-precision data on sea levels, atmospheric variables make future climate impacts complex to forecast.

For more information and to view the latest altimetry data, visit the NASA Earth Observatory or consult the Climate Prediction Center's diagnostic discussions.