Eyeing the future
Predicting the next El Niño should be easy, right? After all, we knew this one was coming. Not exactly, says Glantz. "There are a lot of forecast models out there Š but I would argue that [the forecasters] didn't really get it. You'll probably be reading in the future that they forecast this El Niño in December of 1996, or even November, but they didn't really get it until March of 1997. Actually [at that point] the sea-surface temperatures were warming, and you could see it from the satellites.
"But that's the same time that the Peruvian fisherman -- who had no access to computer models, no Internet capability, maybe even didn't have a television -- stuck his hand in the water and said it's getting warm, something is going on. So here's the question I've been asking now: Did they really forecast this El Niño? Because El Niños can range from weak to extraordinary. This one was extraordinary. And nobody forecast an extraordinary event. Even in June of 1997, when they said this was going to be a big El Niño, they still didn't know how big it was going to be."
Scientists' ability to monitor El Niño -- to follow its developments from day to day -- has gotten to be excellent, Glantz says. "But I would say that forecasting it still has a long way to go."
Why the difficulty in predicting the event? For this most recent El Niño, scientists were caught off guard. The waters in the Pacific started to heat up earlier and faster than during other El Niños in recent years. Though all El Niños seem to go through the same phases from onset to decay each one is capable of throwing a curve. "The truth of the matter is," says Glantz, "we didn't really know about El Niño's global implications until the late 1960s. We started to monitor it in the mid-1980s. So we really haven't seen all the kinds of El Niños that can develop, and all the kinds of impacts they can have."
There have, of course, been some success stories. One pair of researchers used their computer model early in 1986 to successfully forecast the onset of the 1986-87 El Niño. And while the forecast of the 1997-98 El Niño phenomenon wasn't particularly good, some of the projections about its possible impacts were good. "We knew California was going to get slammed," says Glantz. "And there was a good chance that the Gulf states were going to get hit. So people were able to do things to protect themselves." Californians, for example, repaired roofs and cleaned out irrigation ditches to prepare for the onslaught of heavy rains.
That's the importance of an accurate and early forecast: to lessen El Niño's impact by helping society prepare for the event. The research community is beginning to hope that the onset of future El Niños will be predicted four to 12 months in advance. Glantz feels that the potential uses of that information are almost limitless. He points to a wide range of human activities that could benefit: improving agricultural production, for example, or making better trade deals for commodities, or mitigating the many natural hazards that go hand-in-hand with El Niño.
The El Niño of 1997-98, Glantz concludes, was a dry run. "It's the next El Niño that will test how much we've learned about El Niño -- and how to deal with it."
Sonia Ellis, EAS'86, is a freelance writer on science and technology who lives in Colorado Springs, Colorado. Her profile of Associate Professor of Bioengineering Ken Foster appeared in the February Gazette.
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Copyright 1998 The Pennsylvania Gazette Last modified 6/1/98