There is a misconception that El Niño is a type of storm. There are many storms associated with El Niño. However, it is not a storm. It is the warm phase of the El Niño Southern Oscillation.
In a nutshell, it is a phenomenon that can influence weather patterns throughout the world. Varying water temperatures in the eastern Pacific Ocean, particularly around South America, influence weather taking place all over the world. The cold Humboldt Current normally found along the coast of Peru and Chile gets replaced with the warm Equatorial Current. Nutrient rich ocean water, which attracts a variety of fish species, gets replaced with nutrient poor warm waters. The normally arid coast of Peru gets rain. Winters in the Midwest USA/Northwest USA are warmer than normal. Northeast Mexico sees wetter, cooler winters. The western Pacific experiences drought. East Africa gets heavy rainfall between March and May.
Why mention this? This shows how dynamic and broad geography is. Varying ocean temperatures on the west coast of South America can affect the weather in places like Kenya, Australia, the USA, and throughout the world. The warming waters often less fish. This is hard on the fishing industry. This can effect the economy, not only in South America. The next time you buy fish from the super market, check to see where that fish came from.