Devastating El Nino Forecast
Scientists fear ecosystem chaos

Alex Barnum, Chronicle Staff Writer

Thursday, August 14, 1997

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Scientists say a warming of the eastern tropical Pacific Ocean this summer is shaping up to be the strongest -- and potentially most devastating -- El Nino in more than half a century.

Ocean and climate researchers have spent the past three months tracking a gargantuan tongue-shaped slug of warm tropical water sloshing east across the Pacific Ocean to South America -- the telltale sign of a phenomenon that can have profound effects on climate and economies.

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If current predictions hold, this year's El Nino could be at least as strong as the infamous 1982-83 El Nino, the most severe in the past 50 years. That event has been blamed for as many as 2,000 deaths and more than $13 billion in weather-related damages worldwide.

``This is looking to be a fairly massive event,'' said Daniel Cayan, director of climate research division at Scripps Institution of Oceanography in La Jolla. ``It's got us on the edge of our seats.''

El Ninos are notorious for rearranging the world's weather patterns and throwing natural ecosystems out of whack, bringing wild storms to the California coast, droughts to Australia and balmy winter weather to the Northeast. And officials are worrying about the same this year.

El Nino's warm currents and tropical storms typically reach the California coast in the late fall or winter. But this year, federal forecasters are predicting that it will arrive sooner, perhaps as early as September.

Compounding the situation this year is the fact that the ocean off the West Coast of North America is both warmer and higher than normal, which scientists say is part of a little- understood long-term trend that could greatly exacerbate the effects of El Nino.

In California, state officials are worried about a repetition of the winter storms of 1982-83, which brought the highest runoff in the state this century, caused hundreds of millions of dollars of damages along the coast and flooded the Sacramento Valley.

For the first time, the insurance industry on the West Coast plans a major education campaign this fall to help property owners prepare for El Nino-related storms.

Among scientists, however, concern about the effect of storms has to compete with excitement. They view this year's El Nino as an unprecedented opportunity to study one of nature's least-understood phenomena.

``Everyone's excited about this,'' said Stephen Bollens, a biological oceanographer at San Francisco State University. ``There's been a lot of scrambling in the scientific community to get ready.''

Scientists were largely unprepared for the 1982-83 El Nino. Since then, Bollens said, an extensive network of ocean buoys and satellites has been installed to monitor ocean temperatures, sea levels and a variety of other factors.

During an El Nino, easterly trade winds relax or even reverse direction, sending a wave of warm ocean water sloshing across the ocean from Asia to the coast of Latin America and surging up and down the North and South American coasts.

Its name comes from the Spanish for ``the Christ child'' because it typically appears off the coast of Peru and Chile at Christmas.

EARLY TRACKING

Ocean and climate scientists began tracking the growth of an El Nino in May -- much earlier in the year than past El Ninos have started to develop. The waters of the eastern Pacific already are 8 degrees warmer and a foot higher than normal for this time of year.

As a result, scientists say the El Nino's full force may hit the West Coast sooner -- and perhaps harder -- than usual.

``The computer models indicate that the storms will hit California, and they predict three to four times the normal rainfall,'' said Reinhard Flick, an oceanographer with the state Department of Boating and Waterways. ``That's a hellacious amount of rain.''

In California, the effects of an El Nino seem to depend on how severe it is. Strong warming events are associated with wet, stormy winters, while mild El Ninos, such as the one in 1992- 93, are linked to droughts.

In the winter of 1982-83, El Nino churned up huge Pacific storms that slammed into the California coast continuously from December to April. Combined with sea levels about three feet higher than normal, they caused tremendous damage.

The storms stripped tons of sand from beaches, eroded vast sections of coastline, caused mudslides in Malibu and the Santa Cruz Mountains, washed out breakwaters and crashed through the plate glass windows of oceanfront restaurants and houses in Southern California.

In all, 33 oceanfront homes were destroyed and 3,900 businesses and homes were damaged.

WIDESPREAD FLOODING

Inland, recalled Maurice Roos, the state's hydrologist, the storms caused flooding on the upper Sacramento River. Tulare Lake, which was sucked dry during the 1930s and turned into 100,000 acres of farmland, was briefly turned back into a lake for the first time in half a century.

The insurance industry paid out $280 million in four Western states in 1983. This time, insurers plan a major public education campaign starting this fall to help property owners prepare their property for the storms.

``We're hoping to really get in on the front end of it,'' said Candysse Miller, regional director for the Western Insurance Information Service in Los Angeles.

Still somewhat cautious, state officials are not yet telling people to prepare for an unusually stormy winter. But they are increasingly concerned about the possible effect, particularly given the fact that repairs from torrential downpours last winter are still not complete.

``Some levees damaged in January have not yet been restored,'' Roos said. ``I'm not sure they're going to be restored by November. We hope so. We're working on them.''

Meanwhile, biologists are concerned about the havoc an El Nino might play on the marine ecosystem. Warm El Nino water traps the typical upwelling of cold, nutrient- rich water, restricting the food supply in the eastern Pacific, which contains some of the ocean's most productive fisheries.

The collapse of anchovy fishing off the coast of Peru and Chile is perhaps the best-known result of El Nino, but the warming produces a similar, if less dramatic, effect off the West Coast of North America.

Along the California coast, marine biologists are bracing for a big increase this winter in the beach strandings of malnourished sea lions and northern elephant seals because the small fish that they feed on are expected to be less abundant.

During the more moderate 1992-93 El Nino, 2,600 seals and sea lions -- double the number of an average year -- were found stranded on California beaches. At the Marine Mammal Center in the Marin Headlands, volunteers set up makeshift pens in the parking lot to handle the overflow.

``All the rehabilitation centers in the state won't be able to handle the load,'' said Joe Cordaro, coordinator of the California Marine Mammals Stranding Network. ``We'll have a lot of animals on the beach that we can't do anything for.''

SHIFTING OF SPECIES

Another effect is to shift warm- water-loving species farther north. This may delight anglers off the Northern California coast, who have been known to catch bonito, marlin and barracuda, species usually found off the Baja peninsula, in an El Nino year.

James Kelley, an oceanographer and dean of San Francisco State University's School of Science and Engineering, recalls how the waters of Monterey Bay and even parts of San Francisco Bay turned crimson with the influx of millions of tiny tropical red crabs.

Biologists note that this rearranging of the ecosystem can mean trouble for native species. During the 1992 El Nino, mackerel, which are voracious predators, migrated up the coast to British Columbia, devastating the populations of juvenile salmon, including some species considered endangered.

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