\u201cWhile this year\u2019s event started a bit later than the big El Ni\u00f1os of 2015 and 1997, it\u2019s beginning to catch up,\u201d said Josh Willis, a sea level researcher at NASA\u2019s Jet Propulsion Laboratory in Southern California and project scientist for Sentinel-6 Michael Freilich. \u201cWe\u2019ll see how big it gets.\u201d<\/p>\n
Measurements from Sentinel-6 Michael Freilich show a small Kelvin wave forming around Micronesia in late January and dissipating by mid-February. A new wave emerged in early March, then moved east over time. By mid-May, the seas around Peru were more than 5.9 inches (15 centimeters) higher than long-term averages.<\/p>\n
\u201cNASA\u2019s observation of El Ni\u00f1o uses sea level satellites like Sentinel-6 Michael Freilich to track massive Kelvin waves as they cross the Pacific, capture changes in Earth\u2019s ocean thermodynamics, improve forecasts of weather extremes, and help communities prepare for potential coastal hazards,\u201d said Nadya Vinogradova Shiffer, lead program scientist at NASA Headquarters in Washington. \u201cStay tuned as more ocean stories continue to unfold.\u201d<\/p>\n
Tracking El Ni\u00f1o<\/p>\n
Fishermen in the 1600s coined the name El Ni\u00f1o \u2014 Spanish for \u201cthe boy,\u201d a reference to the birth of baby Jesus \u2014 because it tended to intensify around Christmastime. Warmer waters meant they would catch fewer fish.<\/p>\n
Warmer sea surface temperatures in the central and eastern Pacific affect atmospheric circulation patterns worldwide by shifting the jet stream, which impacts storm tracks. This can lead to heavy rain and snow in some areas and unusual heat and dryness in others. How far away those impacts appear depends on the strength of the El Ni\u00f1o.<\/p>\n
In more modest events, like the ones that began in 2018 and 2023, impacts such as drought and flooding were mostly seeb in and around the tropical Pacific. Large El Ni\u00f1os, like the one in 2015-2016, reach much farther, causing drought in Africa and flooding in California.<\/p>\n
El Ni\u00f1os usually peak between November and January, so it will be several months before the largest impacts become clear.<\/p>\n
\u201cEvery El Ni\u00f1o is different,\u201d said JPL sea level researcher Severine Fournier, deputy project scientist for Sentinel-6 Michael Freilich. \u201cBut they almost always make for a hot year and big changes in rainfall in parts of the globe.\u201d<\/p>\n
Sentinel-6 Michael Freilich is the current official reference satellite<\/a> for global sea level measurements. Launched in 2020, it is continuing a legacy started in 1992 by the TOPEX\/Poseidon satellite. A series of successors have carried the baton since then, and the latest, Sentinel-6B, which launched<\/a> November 2025, will take over for its predecessor by the end of 2026.<\/p>\n More about Sentinel-6 Michael Freilich<\/p>\n Sentinel-6 Michael Freilich, named after former NASA Earth Science Division Director Michael Freilich, is one of two satellites that compose the Copernicus Sentinel-6\/Jason-CS (Continuity of Service) mission.<\/p>\n Sentinel-6\/Jason-CS, a part of the European Union\u2019s Earth observation programme called Copernicus, was jointly developed by ESA, the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), NASA, and the National Oceanic and Atmospheric Administration (NOAA), with funding support from the European Commission and technical support on performance from the French space agency CNES (Centre National d\u2019\u00c9tudes Spatiales). Spacecraft monitoring and control, as well as the processing of all the altimeter science data, is carried out by EUMETSAT on behalf of the European Union\u2019s Copernicus Programme, with the support of all partner agencies.<\/p>\n A division of Caltech in Pasadena, JPL contributed three science instruments for each Sentinel-6 satellite: the Advanced Microwave Radiometer<\/a>, the Global Navigation Satellite System – Radio Occultation<\/a>, and the Laser Retroreflector Array<\/a>. NASA also contributed launch services, ground systems supporting operation of the NASA science instruments, the science data processors for two of these instruments, and support for the U.S. members of the international Ocean Surface Topography Science Team.<\/p>\n To learn more about Sentinel-6 Michael Freilich, visit:<\/p>\n