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El Nino Forecasts Flop as Puzzled Scientists Search for Answers

By | February 6, 2015

When it comes to El Nino, 2014-15 may be the years that launched a thousand academic papers.

Since last March, forecasters have said an El Nino was on the way. The only trouble is, it hasn’t arrived. Call it the period of the phantom El Nino, a shimmering siren of weather patterns yet to come that has been seen fluttering in the sparkling waters of the equatorial Pacific Ocean.

While every El Nino sparks research, this one — or the lack thereof — is certain to prompt even more. Part of the reason is that while some global weather patterns reacted as though an El Nino was taking place, the main characteristics of the phenomenon never materialized. If there’s anything scientists hate, it’s not understanding why something happened.

“One thing that stands out on this ENSO is how wrong the models were in predicting a major event in 2014,” said Matt Rogers, president of Commodity Weather Group LLC in Bethesda, Maryland.

An El Nino occurs when the area’s surface warms above normal and there is a corresponding reaction in the atmosphere that changes weather patterns around the world. The process is called the El Nino/Southern Oscillation, or ENSO for short.

The equatorial Pacific has warmed a few times in the past year, yet there was no reaction in the skies above it.

Earlier this week, the Australian Bureau of Meteorology said the area is now in a neutral state and has entered the time of year when “ENSO events naturally decay.”

Caution Urged

“Forecasting beyond this time is therefore difficult, and some caution should be exercised,” the agency said. “International models surveyed by the bureau indicate that tropical Pacific sea-surface temperatures are likely to remain within the neutral range for at least the next three months.”

The U.S. Climate Prediction Center sets odds of 50-60 percent that an El Nino will form. Last month, it predicted development by March, while in a new assessment Thursday it extended the timeline to “early spring.” The U.S. uses slightly different criteria than Australia, so it isn’t a one- to-one comparison of data.

Japan’s Meteorological Agency, which also issues updates on the Pacific, has said El Nino-like conditions have occurred across the ocean even if the atmosphere hasn’t reacted. This isn’t as far out as it sounds, because sea-surface temperatures have flirted with being warm enough for an El Nino to form.

The warming of the ocean has also triggered some other patterns that often occur when an El Nino forms. Some sea birds along the coasts of North and South America, including Cassin’s Auklets, have died in large numbers, said Andrew Farnsworth, a researcher with Cornell University’s Ornithology Lab.

Dying Birds

They starved because the warmer waters forced the sea creatures they eat to leave. There have also been examples of other bird species flying outside their normal ranges searching for sources of nourishment, Farnsworth said.

Other El Nino indicators have been mixed at best. In April, some researchers believed a strong El Nino might be on the way and that would lead to the world having its warmest year on record.

Well, the strong El Nino didn’t show up and the world still had its warmest year on record, U.S. weather and space agencies said last month.

Pattern’s Effect

The U.S. northeast can have mild winters in El Nino years while winter in the South can be stormier. December was warmer than normal across much of the Northeast, while January wasn’t. New York’s Central Park registered an average temperature of 29.9 degrees Fahrenheit (minus 1.2 Celsius) in January, or 2.7 degrees below normal, the National Weather Service said.

The storm track across the U.S. often drops south in an El Nino year, bringing more rain and snow to California and the mid-Atlantic states. San Francisco just had its driest January in 165 years, with no rain at all.

An El Nino can cause drought conditions across Brazil. While there has been dryness there, the cause is a pool of warmer water in the Atlantic, Joel Widenor, a meteorologist at Commodity Weather Group LLC in Bethesda, Maryland, said last month.

Now the world is entering the time of year when it is hard to forecast what El Nino is going to do. Between March and May, computer models often have trouble making sense of what is happening in the Pacific.

Here’s one prediction that you can probably count on:
“Just the fact that there was just heightened attention to the possibility of an El Nino, there is a greater likelihood that there will be a lot of scientific publication,” said Michelle L’Heureux, a meteorologist with the Climate Prediction Center in College Park, Maryland.

Topics Trends USA Maryland

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