El Niño Scorecard
by Mark Hoover
The great 1997 El Niño snuck up on us. Once here, it seemed to spawn an
entire industry last year, the business of El Niño forecasting. We kept
track of some of the major predictions, matched them up with what actually
happened, and tabbed the results to get a sense of just how good the
forecasters have gotten.
Northern US and Canada |
India and Oceania |
Eastern Pacific and Western Atlantic
Date of Appearance
Prediction: Before El Niño actually showed up, many forecasts said 1997
might be an El Niño year; many said not. It wasn't until late February
or March that scientists put the pieces of the puzzle together and realized El
Niño was underway. As NOAA's Michael Glantz wryly put it, "once it was
started, it wasn't as hard to predict."
Outcome: The ayes had it. But no one predicted it would be a
record-breaker; most thought it would be weak and short-lived.
Prediction: In early autumn last year Ants Leetmaa, the director of NOAA's
National Center for Environmental Prediction, warned Californians of a long
winter of powerful storms comparable to the devastating storms in the El
Niño winter of 1982-83. Specifically, he said "The southern part of the
state can expect rainfall on the order of 200% of normal."
Outcome: El Niño deflected the two major northern jetstreams so that
they carried a long train of storm systems into the state throughout the
winter. Southern California got double its average winter rainfall, recording
approximately 230% of normal. Flooding was widespread in several coastal
areas, with regions near San Francisco suffering especially.
The Northern US and Canada
Prediction: The northern half of the US was predicted to experience a
relatively mild winter, as the jetstream could be expected to park itself
farther north than usual, acting as a barrier against cold Canadian air.
However, especially along the east coast, intrusions of southern moisture might
lead to more rain and storms than usual.
Outcome: The northern US generally enjoyed a mild winter. One way to measure
is the total expenditure on heating fuels; the average heating bill over the
winter was as much as 10 percent lower than normal.
Prediction: Peru would be inundated by heavy rains throughout the peak of the
El Niño occurrence, and cooler waters off the coast would mean a drop in
Outcome: Peru and adjacent Ecuador suffered massive flooding, with rains rarely
stopping for months on end. In January and February, the land could absorb no
more water, and vast new lakes—some 50 miles long—appeared in formerly
dry coastal areas. Rivers ripped out entire towns in the mountains, and
completely inundated agricultural areas in valleys. At sea, fish stocks were
depressed, and many fishermen suffered severe economic pain.
Prediction: Australia would wither under an extended drought throughout the
northern winter (which in Australia and the Southern Hemisphere is summer).
Outcome: This one's a toss-up; as NOAA's Mickey Glantz put it, "the
(forecasting) operation was a success, but the patient died." Meteorologically
speaking, there was a bad drought, as rainfall totals across Australia were
well below normal. But agriculturally speaking, enough rain fell at just the
right times to prevent catastrophic wheat crop and cattle losses. Australian
newspapers gave thanks to "Billion-Dollar Rains" that appeared just as disaster
seemed imminent, showing that it's not how much rain you get, but when you get
it, that counts.
India and Oceania
Prediction: India and Oceania would suffer a failure of vital monsoons (heavy
Outcome: The monsoons had a late onset, showing up many weeks later than
normal, but although erratic in schedule, were in no sense "failed." Indonesia
in particular suffered a self-inflicted wound, as fires deliberately set to
clear forest lands for slash-and-burn agriculture raged out of control when the
monsoons took their time arriving. Fears of imminent famine and misery in
India disappeared with the onset of the life-giving rains, although coastal
China was flooded and battered by an excess of violent storms bearing tornadoes
and high winds.
Prediction: Southern Africa would suffer drought and severe food shortages,
followed by increases in disease.
Outcome: There was very little noticed effect on weather, no major drought,
and no widespread outbreaks of disease or famine.
Eastern Pacific/Western Atlantic
Prediction: The Eastern Pacific would engender some very powerful hurricanes,
while Atlantic hurricane production would be suppressed.
Outcome: Some of the most powerful hurricanes ever measured spun up in the
Pacific, including Hurricane Linda, so powerful that weather scientists
proposed a new "Category 6" (the current system only goes up to 5) to describe
it. (Compare Linda, with winds of 185 mph, to Andrew, the hurricane that
devastated Homestead, Florida in 1994 with winds of 130 mph.) Meanwhile, the
Atlantic hurricane season was below normal.
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© | Updated November 2000