CLIMATE OF INDIA
EL NINO AND SOUTHERN OSCILLATIONS
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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El Nino
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La Nina
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Neutral year
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none of above
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Detailed explanation-1: -During an El Niño event, westward-blowing trade winds weaken along the Equator. These changes in air pressure and wind speed cause warm surface water to move eastward along the Equator, from the western Pacific to the coast of northern South America.
Detailed explanation-2: -“During an El Niño year, weakening winds along the equator lead to warming water surface temperatures that lead to further weakening of the winds.” The image below shows the dominant direction of the winds and changes in their intensity near the ocean surface as observed by NASA’s RapidScat instrument.
Detailed explanation-3: -An El Niño condition occurs when surface water in the equatorial Pacific becomes warmer than average and east winds blow weaker than normal. The opposite condition is called La Niña. During this phase of ENSO, the water is cooler than normal and the east winds are stronger. El Niños typically occur every 3 to 5 years.
Detailed explanation-4: -During an El Niño event, the easterly trade winds converging across the equatorial Pacific weaken.
Detailed explanation-5: -During El Niño, the surface winds across the entire tropical Pacific are weaker than usual.