What North America Can Expect From El Niño

A major El Niño is under way now. It already has substantially influenced weather patterns around the globe, but could have even bigger impacts this winter.
What North America Can Expect From El Niño
A sand berm created by city workers to protect houses from El Nino storms and high tides is seen at Playa Del Rey beach in Los Angeles, California on November 30, 2015 at the start of the COP21 conference in Paris. MARK RALSTON/AFP/Getty Images
Updated:

A major El Niño is under way now. It already has substantially influenced weather patterns around the globe, but could have even bigger impacts this winter. There have been only two “super” El Niños: in 1982–1983 and 1997–1998. We are now experiencing a third “super” El Niño.

Every El Niño cycle is different. The effects from this year’s already include a record number of hurricanes/typhoons in the Pacific and intense wildfires in Indonesia.

In the United States over the next several months, El Niño is expected to cause heavy rains across the South, with the potential for coastal flooding in California, along with relatively mild and dry weather in the northern states. Global climate change, which, along with the El Niño, is making 2015 the warmest year on record, is likely to amplify these impacts.

What Is El Niño?

El Niños are not uncommon. Every three to seven years or so, the surface waters of the tropical Pacific Ocean become extremely warm from the International Dateline to the west coast of South America. This process causes changes in the local and regional ecology, and is clearly linked with abnormal global climate patterns.

The Oceanic Niño Index (ONI) shows warm (red) and cold (blue) phases of abnormal sea surface temperatures in the tropical Pacific Ocean. (NCAR/Author provided)
The Oceanic Niño Index (ONI) shows warm (red) and cold (blue) phases of abnormal sea surface temperatures in the tropical Pacific Ocean. NCAR/Author provided
Kevin Trenberth
Kevin Trenberth
Author
Author’s Selected Articles
Related Topics