CLIMATE OF INDIA
EL NINO AND SOUTHERN OSCILLATIONS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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higher than average
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lower than average
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average
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none of above
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Detailed explanation-1: -Unlike El Niño years, the impacts of La Niña often continue into the warm months. In eastern Australia, the average December-March rainfall during La Niña years is 20% higher than the long-term average, with eight of the ten wettest such periods occurring during La Niña years.
Detailed explanation-2: -La Niña is related to increases in the likelihood of above-and below-average precipitation over many regions of the globe (Fig. 2). These changes in precipitation likelihoods occur during certain times of the year.
Detailed explanation-3: -During El Niño the trade winds weaken, releasing heat to the atmosphere and the warm pool and rainband shift to the east, causing dry and hot conditions in Australia. During La Niña, the trade winds and warm pool intensify, leading to more rainfall and lower temperatures in Australia.
Detailed explanation-4: -Sometimes higher-than-normal temperatures occur during El Nio events, mainly because of increased daytime maxima. Higher surface maxima may imply more frequent thunderstorms, and in fact, the higher the SOI (i.e. under La Nia conditions) the higher the continent-average amount of rain per rain event in Australia.