Why does El Niño and La Niña occur?

El Niño and La Niña are naturally occurring phenomena that result from interactions between the ocean surface and the atmosphere over the tropical Pacific.

Changes in the ocean surface temperatures affect tropical rainfall patterns and atmospheric winds over the Pacific ocean, which in turn impact the ocean temperatures and currents.

The El Nino and La Niña related patterns of tropical rainfall cause changes in the weather patterns around the globe.

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High Low
Current 37°F 29°F
Average 51°F 30°F
Record 84°F March 21, 1921 10°F March 21, 1965