These color-coded images show the strengthening of El Niño between October and November 2009. In the November image, warm waters (indicated in red) have spread across the Pacific.
Published Dec 11, 2009
Past events suggest the phenomenon winds down after December and January. But will this year follow the pattern?
Published Jan 22, 2016
Cooler than normal conditions prevail in the central and eastern Pacific, but the event is so far considered weak.
Published Dec 22, 2017
The near-record water temperatures of 2015-16 has been followed by a modest, quiet appearance of La Niña.
Published Jan 6, 2017
Weakening trade winds are allowing warm water to move east across the Pacific in a telltale pattern.
Published Aug 5, 2015
Ocean conditions are not likely to help drought-stressed regions this spring. However, some broader changes might be coming in the Pacific.
Published Mar 25, 2015
The cool water anomaly in the center of the image shows the lingering effect of the year-old La Niña. However, the much broader area of cooler-than-average water off the coast of North America from Alaska (top center) to the equator is a classic feature of the cool phase of the Pacific Decadal Oscillation (PDO).
Published Apr 29, 2008
Conditions in May 2014 look similar to those in May 1997, a year that brought one of the most potent El Niño events of the 20th century.
Published May 14, 2014
With its own forms of underwater weather, the ocean has fronts and circulation patterns that move heat and nutrients around its basins. Changes near the surface often start with changes in the depths.
Published Mar 21, 2017
With each passing month, 2015 looks more and more like 1997.
Published Oct 13, 2015
After appearing for two consecutive winters, La Niña appears to be taking some time off.
Published May 4, 2012
