Photo Credit: NOAA

A relatively new type of El Niño, which has its warmest waters in the central-equatorial Pacific Ocean, rather than in the eastern-equatorial Pacific, is becoming more common and progressively stronger, according to a new study by NASA and NOAA. The research may improve our understanding of the relationship between El Niños and climate change, and has potential significant implications for long-term weather forecasting.

The scientists say the stronger El Niños help explain a steady rise in central Pacific sea surface temperatures observed over the past few decades in previous studies — a trend attributed by some to the effects of global warming. While Lee and McPhaden observed a rise in sea surface temperatures during El Niño years, no significant temperature increases were seen in years when ocean conditions were neutral, or when El Niño’s cool water counterpart, La Niña, was present.

“Our study concludes the long-term warming trend seen in the central Pacific is primarily due to more intense El Niños, rather than a general rise of background temperatures,” said Lee.

http://www.noaanews.noaa.gov/stories2010/20100825_elnino.html#