Study Sounds ‘El Niño Alarm’ For Late This Year

A new study shows that there is at least a 76 percent likelihood that an El Niño event will occur later this year, potentially reshaping global weather patterns for a year or more and raising the odds that 2015 will set a record for the warmest year since instrument records began in the late 19th century.

The study, published on Monday in the Proceedings of the National Academy of Sciences, builds on research put forward in 2013 that first proposed a new long-range El Niño prediction method. 

Image of the Pacific Ocean showing sea surface height measurements taken by the U.S. and French TOPEX/Poseidon satellite. The image shows sea surface height relative to normal ocean conditions on Dec. 1, 1997. In this image, the white and red areas indicate unusual patterns of heat storage, indicative of strong El Niño conditions.
Credit: NASA

Although they occur in the equatorial tropical Pacific Ocean, the effects of El Niño events can reverberate around the globe, wreaking havoc with typical weather patterns. El Niños increase the likelihood for California to be pummeled by Pacific storm systems, for example, while leaving eastern Australia at greater risk of drought. Because they are characterized by higher than average sea surface temperatures in the equatorial tropical Pacific Ocean, and they add heat to the atmosphere, El Niño events also tend to boost global average temperatures.

By acting in concert with manmade greenhouse gases, which are also warming the planet, calendar years featuring a strong El Niño event, such as 1998, can more easily set all-time high temperature records.

Today, scientists can only reliably predict the onset and severity of El Niño events by about 6 months ahead of time. And this lead time may actually decrease due to Congressional budget cuts for ocean monitoring buoys that provide crucial information for El Niño forecasting.

The new study, by an international group of researchers, takes a starkly different approach to El Niño forecasting compared to conventional techniques. While the forecast models in use today tend to rely on observations of the ocean conditions and trade winds that generally blow from east to west across the tropical Pacific, the new method relies on an index that compares surface air temperatures in the area where El Niño events typically occur with temperatures across the rest of the Pacific.

http://www.climatecentral.org/news/study-sounds-el-nino-alarm-for-2014-17052