NASA spots El Niño precursor from space: 'If it’s a big one, the globe will see record warming'

Satellite image of Earth showing areas of the Pacific ocean that are warmer and higher - a sign of El Nino (Image credit: NASA/JPL-Caltech)

NASA has identified early signs of El Niño from space, after one of its satellites spotted warm water in the Pacific Ocean moving eastward toward the west coast of South America in March and April. 

Data from the Sentinel-6 Michael Freilich satellite, which monitors sea levels, showed Kelvin waves moving across the Pacific. These long ocean waves are just 2 to 4 inches (5 to 10 centimeters) high but are hundreds of miles wide. They are considered to be a precursor to El Niño when they form at the equator and move the warm upper layer of water to the western Pacific.