One More Time! The Troubles with Predicting El Niño

January 29, 2016
Flooded River

Rate this Post: 

Average: 5 (2 votes)

It was so-o-o easy. Scientists would predict an El Niño. Boom—three months later, the El Niño would arrive.

In North America, it brought cozy warm winters, rainy days in California, few hurricanes and excellent crop conditions. Summers were cooler, food cheaper and good times were had by most Americans.

It used to be easy to predict El Niños that would bring California lots of rain. Source NOAA

Sigh! Those were the days.

Now scientists say that we are experiencing El Niño conditions and will probably have an El Niño this summer. Just one problemthe last few times they predicted an El Niño, they were wrong!

Here’s the problem: The Pacific is complicated. The El Niño/La Niña is only one of many cycles in the ocean that covers 30% of the globe. An even bigger cycle is messing with the scientists’ models and predictions.

Over the past few years, the trend towards Negative PDOs has made El Niños less common.

Welcome to the PDO! It means Pacific Decadal Oscillation, a 50+ year cycle that shifts warm and cold water around the Pacific. You can remember it as Pretty Dry Oklahoma. In the positive phase, the Tropical and Eastern Pacific tend to be warm. In the cool negative phase, we see the reverse. Each phase, warm or cool, lasts for decades (which is why it was called decadal.)

It and the El Niño interact. When the trend was positive, it was easy to predict warm El Niños. They tend to be strong and their impact on American rainfall is good. When the trend is negative and cold, it is hard to develop and they tend to be weak and don’t last very long.

When the trend was warm and positive, we had an El Niño every four years. Since 2006 the trend has tended to be negative and we have only had one event. Bad news for El Niños, California rainfall and scientists trying to predict either.  Every other time, when an El Niño started to develop, like in 2012 and last year, it failed.

Scientist say there is a good chance of an El Niño most of the rest of this year. Source: NOAA

So if scientists are predicting an El Niño, just remember the Pacific is a really crazy ocean. It is getting a lot less predictable. 


About This Blog

Are you a weather watcher? Welcome to “Weather Whispers” by James Garriss and until recently, Evelyn Browning Garriss. With expertise and humor, this column covers everything weather—from weather forecasts to WHY extreme weather happens to ways that weather affects your life from farming to your grocery bill. Enjoy weather facts, folklore, and fun!

With heavy hearts, we share the news that historical climatologist and immensely entertaining Almanac contributor Evelyn Browning Garriss passed away in late June 2017. Evelyn shared her lifetime of weather knowledge with Almanac editors and readers, explaining weather phenomena in conversation and expounding on topics in articles for the print edition of The Old Farmer’s Almanac as well as in these articles. We were honored to know and work with her as her time allowed, which is to say when she was not giving lectures to, writing articles for, and consulting with scientists, academia, investors, and government agencies around the world. She will be greatly missed by the Almanac staff and readers.