Fill in each blank with ONE suitable word.
EL NINO AND LA NINA
The tropical Pacific Ocean (1) a warming and coolingcycle. This cycle (2) a completely natural event and usually (3) every three to seven years.
When the waters become (4) , it is called El Nino, and when they become cooler it is called La Nina. During the cycle, the (5) of the ocean can change by around 30C between the warmest and coolest times.
(6) of the South American coast have knownabout this (7) event for hundreds of years. When it (8) , they see a huge fall in the numbers of fish caught. (9) scientists are only just beginning to (10) how the event affects Earth’s weather and climate.
