NASA - National Aeronautics and Space Administration

Image above: The image shows what happens when a very strong El Nino strikes surface waters in the Central equatorial Pacific Ocean. The sequence shows warm water anomalies (red) develop in the Central Pacific Ocean. Winds that normally blow in a westerly direction weaken allowing the easterly winds to push the warm water up against the South American Coast. Click on image to enlarge. Click here for high resolution TIF image (17.4 MB) . Credit: NASA

Image above: This image shows colder than normal water (blue) anomalies in the central equatorial Pacific associated with La Nina. Stronger than normal trade winds bring cold water up to the surface of the ocean. Click on image to enlarge. Credit: NASA

Image above: This image shows the current El Nino's split personality. Warm waters develop in the central Pacific Ocean. In this case, the warm water anomalies tend to stay in place in the central Pacific. Click on image to enlarge. Click here for high resolution TIF image (17.4 MB). Click here to view an animation of El Nino, La Nina and the split. Credit: NASA

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NOAA U.S. Winter Outlook Update

Krishna Ramanujan
Goddard Space Flight Center