The climate phenomenon "El Niño" was named by fishermen off the Pacific coast of South America who noticed occurrences of unusually warm water. Because El Niño-Southern Oscillation occurred around Christmastime, the fisherman named the condition "El Niño" as a reference to Jesus.
El Niño is a temporary reoccurring climate change that occurs in the Pacific Ocean in which sea surface temperatures heat up, causing other weather-related changes worldwide. El Niño occurs when equatorial westerly winds diminish, allowing the surface of the Pacific Ocean to become warmer. El Niños occur approximately every two to seven years, lasting several months from late fall into spring.