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El Nino and La Nina
In recent years, people have shown growing concern about the climatic phenomena of El Nino and La Nina. People often regard them as the culprits for unusual weather or the subsequent disasters, e.g., the forest fires in Indonesia, the snowstorms in North America, the persistent droughts in Africa, etc.
El Nino and La Nina are both natural phenomena. El Nino means ˇ§the Christ Childˇ¨ in Spanish and is used to describe the unusual warming of the coastal sea water in the tropical east and central Pacific Ocean. La Nina means ˇ§the little girlˇ¨ in Spanish. It is the opposite of El Nino and is used to describe the unusual cooling of coastal sea water in the tropical east and central Pacific Ocean.
For example, during late 1997 and early 1998, when the El Nino phenomenon was getting mature, the sea temperature of the above-mentioned waters was 4 to 5 degrees Celsius higher than normal. In contrast, La Nina gestated from June 1998, and by November, the sea temperature of the waters was 1 to 2 degrees Celsius lower than normal.
Generally speaking, the influence of El Nino and La Nina on climate are opposite to each other. For example, when the El Nino phenomenon takes place, countries in the west Pacific region such as Indonesia and Australia are vulnerable to droughts, while countries in the east Pacific region such as Peru and Ecuador get more rainstorms than usual. In contrast, La Nina will bring floods to Indonesia and Australia and deprive Peru and Ecuador of rainfall.
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