21世纪大学英语读写教程第二册09

UNIT 9

Text A

Pre-reading Activities
First Listening
1. As you listen to the passage the first time, circle the words from the list that you hear.
ice hate perish snow fear suffice frost despair hold with rain desire know of fire sorrow wonder fog confusion suffer wind corruption favor

Second Listening
2. Natural disasters are as fascinating as they are frightening. What forms do they take, and what do you know about their causes?

Get Ready for Some Wild Weather

Per Ola & Emily D'aulaire

In March of 1997, Stephen Zebiak stared at his computer screen in alarm. The veteran climate researcher saw indications of a worldwide weather event that, over the years, has been blamed for droughts and floods, famine, fires and thousands of deaths. Called El Nino, it is the most disruptive climatic phenomenon on the planet.
Zebiak and Mark Cane, research scientists at Columbia University, had developed a computerized forecast model that correctly predicted El Nino's occurrences in 1982, '86 and '91, and it had pointed to a recurrence in '98. But the data appearing on Zebiak's screen from satellite and sea-surface monitors across the Pacific were unmistakable: El Nino was already beginning. A huge pool of warm water — larger than the United States and some 600 feet deep — was moving slowly but surely eastward toward South America.
In June the equatorial trade winds reversed direction from westward to eastward. By September, waters off Northern California were roughly 17 degrees warmer than normal. Off the Washington coast, stunned fishermen caught tropical fish that seldom stray that far north. Storms were flooding central Chile, and heavier-than-normal snowfalls in the Andes trapped hundreds in the bitter cold. And all of this only foretold of even more devastating weather for the fall and winter.
El Nino means "little boy" in Spanish; when capitalized, it refers to the Christ child. This innocent-sounding name originated in the 19th century, when Peruvian sailors noticed that every few years around Christmastime, waters near the coasts warmed up and the current shifted southward. But this "little boy" plays havoc around the globe.
El Nino occurs when weather patterns in the tropical Pacific shift violently. Normally, strong westward-blowing trade winds off South America push surface water toward Asia. Just as blowing on hot coffee pushes the liquid up against the opposite side of the cup, the trade winds pile warm water against the coastlines of Australia, Indonesia and the Philippines. Above the warm water, moist air rises, lowering atmospheric pressure and triggering the tropical showers that nourish the rain forests of Asia. Meanwhile high-altitude winds travel back toward South America. There, the cooled air sinks, raising atmospheric pressure and suppressing rain along most of the Pacific coast, making it one of the driest regions in the world.
But with El Nino, the pattern reverses. Atmospheric pressure in the Western Pacific rises, setting the stage for drought from Australia to India. The trade winds decrease, or in extreme years reverse to blow eastward. As a result, a huge mass of warm water flows back toward South America, causing storms from Chile to California. Meanwhile, over the Pacific, ten-mile-high storm clouds further heat the atmosphere, fueling a stronger-than-normal jet stream, which often splits in two. One branch moves north, warming the Pacific Northwest, central Canada and Alaska. Another branch surges south, producing heavy rains in the U.S. Gulf States and Southwest.
El Nino's vast impact on humans has often been catastrophic. The El Nino of 1982-83 inflicted $13 billion in damage and claimed some 2,000 lives. In Australia day turned to night when a dust storm blanketed Melbourne; brush fires raged in its wake. In place of its normal monsoon, Southern India got dried-up crops and the threat of mass starvation. At the same time, violent rainstorms devastated the Western Hemisphere: Peru's fishing industry — once one of the richest in the world — was wiped out, and seaside towns were washed into the Pacific.
Is there a good side to El Nino? There can be. Zebiak notes that the number of tropical hurricanes in the Atlantic is reduced during an El Nino year. One theory is that winds created by El Nino shear off the tops of Atlantic hurricanes, aborting them before they reach full force. And a team of scientists in Israel who study tree rings and satellite cloud pictures concluded that El Nino may bring precious moisture to the thirsty Middle East. "It is perhaps fitting that El Nino — the Christ child — should have a link to the Holy Land," notes scientist Dan Yakir.
This year, scientists around the world are keeping a sharp eye on El Nino. They know that the greater the temperature rise in Pacific waters off South America, the more powerful the El Nino. And this year's waters have heated up unusually fast. Climate-change researcher Michael Ghil of UCLA expects the impact to be "substantial." Ants Leetmaa, director of the National Oceanic and Atmospheric Administration's Climate Prediction Center in Maryland, agrees: This El Nino is shaping up as one of the most powerful ever.
According to forecasters, hardest hit in this country will likely be California, where heavy rains can send houses sliding down muddy slopes onto washed-out coastal highways. The nation's southern states — from California to Florida — can expect cooler and wetter weather than normal this winter and spring, with extensive storms in some areas. The Northwest should be warmer and drier than normal.
Wetter-than-normal conditions are expected in much of South America. The Asian monsoon rains could fail, resulting in food shortages in India. In Australia, where El Nino ypically means drought, strict water conservation is already under way.
El Nino's effects won't just be climatic, of course — the global economy is sure to suffer as well. Drought in Brazil and flooding in Colombia may result in higher prices for coffee and other crops. And fishing industries from Ecuador to California are already being hurt.
Clearly, the more accurately scientists can forecast El Nino, the more people everywhere can prepare. Insurance companies, farmers, power and irrigation companies, public-safety agencies and even tourist boards could benefit from knowing in advance when El Nino will strike.
"Reliable forecasting is still in its infancy," states Mark Cane. Someday, perhaps, scientists will be able to predict exactly how El Nino will behave. But for now, batten down the hatches and get ready for some wild weather!
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