Read the following passage and circle A. B. C. or D to indicate the correct answer to each of the questions.
El Niño and La Niña
Typically, Pacific trade winds blow from east to west, transporting warm surface waters westward, east of Indonesia and northeast of Australia. Thus, the water maintains a cold temperature for much of the year. This is achieved by an upwelling of cold deep ocean-water, which benefits fisheries in the Pacific Ocean lying near the equator. However, these trade winds sometimes lose or gain strength in the Northern Hemisphere. This leads to an effect known as the Southern Oscillation which refers to the two recurring weather patterns of El Niño and La Niña.
El Niño, meaning the "boy," is the phenomenon that results in the temperature of the sea surface off the coast of Peru increasing. This condition typically lasts for at least six months. Thus, there is a reduction in dissolved oxygen in the ocean so marine life declines devastating fisheries. It also fuels major differences in air pressure near the Pacific Ocean, which in turn leads to more severe weather events including droughts, increased precipitation, flooding, and even cyclonic storms like hurricanes. Usually, the eastern Pacific region has an upswing in heavy rains to cause flooding, and in contrast, Australia and Indonesia have droughts, often with accompanying forest fires. These two opposing weather events hurt agriculture. For instance, the 1982 – 1983 El Niño, recognized as the worst weather event of the century, hit hard in the U.S. by dropping huge amounts of rainfall on the southern California coast, which resulted in millions of dollars of damage while necessitating the evacuation of 10,000 people.
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