Scientists fear worst but El Nino could fizzle

Saturday, Oct. 11, 1997 | 7:41 a.m.

Southern Nevada is bracing for an El Nino that could bring the heaviest winter rains this century.

But because of its unpredictability, some scientists aren't sure the deluge is coming.

"El Nino is a big player on the stage" of western U.S. weather, said Kelly Redmond, deputy director of the Western Regional Climate Center of the Desert Research Institute, a research arm of the University of Nevada System based in Reno.

"The odds are good for greater rainfall this winter," Redmond said.

But Nevada climatologist John James takes a skeptical view of the El Nino impact on the Silver State.

"Sometimes a big El Nino leaves Nevada high and dry," he said. "I don't believe the El Nino is the only thing to forecast."

The jet stream, ocean storms and patterns worldwide will all affect El Nino's power, he said.

People's effect on the lay of the land, such as urbanization, plus volcanic eruptions from around the world, must be taken into consideration before predicting anything, James said.

"El Nino has given us both wet and dry conditions," he said, "and the state is big. It reacts differently."

El Nino blankets the eastern Pacific Ocean with extremely warm waters near Peru. It has long baffled weather experts who have struggled to predict exactly what El Nino will do in a particular area.

The 1982-83 El Nino, regarded as the strongest this century, was not even recognized by scientists in its earliest stages. But it wound up being responsible for the deaths of 2,000 people worldwide and it was blamed for $8 billion-$13 billion in economic losses.

By contrast, the upcoming El Nino is the most closely observed in history. Sophisticated equipment on ships, satellites and stationary bouys is gathering floods of data that are being analyzed by computers and scientists worldwide.

Early on, the studies revealed that the Pacific Ocean off Peru was 9 degrees warmer than normal. That warmer water stretched westward along the equator to the international dateline.

But that could mean just about anything will happen as observers prepare for the worst and hope for the best.

For the Las Vegas Valley, the effects of El Nino are unpredictable, said Chief Meteorologist Larry Jensen of the National Weather Service.

"Definitely, the Southwest coast could get very wet," Jensen said, basing his statement on a new system of satellites beaming temperature, pressure, wind patterns and ocean temperature and its flow to scientists around the world.

"The warm water has already reached into Southern California," he said. "It definitely is a very big event."

The last three major El Ninos behaved differently over Southern Nevada each time, Jensen noted.

Normally, August and September temperatures in Las Vegas are four to five degrees cooler before an El Nino, he said. This year the pattern has not held true.

When El Nino isn't around, rain from October through April falls roughly under three inches, which is about 75 percent of Southern Nevada's annual rainfall.

In 1982-83, 3.46 inches of rain fell, compared with the El Nino winter of 1972-73 when 6.71 inches pounded Southern Nevada.

Based on the size of this year's Pacific warming, six to nine inches of rain could fall, Jensen said.

Still, no weatherman worth his weather vane knows how destructive this winter will be, Jensen said.

"Let's go crazy," Jensen said. "What if we get nine inches of rain? The next question is how does it fall?"

If it comes slowly -- a fraction of an inch per hour -- the valley can handle it. But if it comes by the inch or more per hour, then there could be flooding with potential threats to life and property.

"It's irresponsible for anyone to say we'll have major problems -- yet," he said.

The U.S. Soil Conservation Service has documented 184 different floods -- regardless of whether El Nino is at work -- that damaged public and private property in Southern Nevada.

Since 1960 the area has experienced at least seven "million-dollar floods," the agency said, noting that in the same period, 22 people died in nine separate flash flood events.

Southern California expects "unusual" weather patterns, said Jay Malinowski, chief of operations for the Los Angeles Metropolitan Water District. "Weather, especially in California, is too unpredictable," he said.

"Unpredictability aside, we're anticipating higher-than-normal precipitation in 1997-98," Malinowski said.

Records of El Nino events in at least five languages date back more than 450 years, according to one study.

Since 1525, 33 years after Columbus discovered the New World, there have been 47 major El Nino events, according to a study by the College of Oceanography at Oregon State University.

William Quinn and Victor Neal, authors of the report published 10 years ago in the Journal of Geophysical Research, studied the documents kept by ship captains, navigators, historians and even the clergy who accompanied early Spanish explorers.