The Pasadena lab said Tuesday that a Dec. 27 image of ocean warming produced by data from its Jason-2 satellite is strikingly similar to one from December 1997 during a previous large El Nino event.
The spacecraft measures sea surface heights, which indicate a thick layer of warm water when they are higher than normal.
The latest image and the 1997 image both show unusually high sea surface heights along the equator in the central and eastern Pacific.
El Ninos are linked to dramatic alteration of weather around the world. The current El Nino’s effects in the U.S. are expected to appear in early 2016.