What is El Niño?

El Niño is a weather phenomonenon that happens every 2-7 years. It was named El Niño by Peruvian fisherman who noticed that every couple years around Christmas there were no fish to catch (El Niño means the child, like baby Jesus).

Basically what happens is that the waters in the eastern Pacific by the equator get too warm. That means more clouds form. And that means more rain. Usually the warm of surface waters is picked up by the dominant East-West winds that are a result of the Earth's rotation, and then the resulting clouds are carried West.* But in an El Niño year there's just too much warmth to be taken away by the waves.

The resulting effects are hard to predict beyond "things get weird." There's usually torrential rain in the northern parts of Peru. But other parts of Peru (and the world) see droughts instead. It might mean a lot of rain in California, which could be good in terms of bringing some water, but bad in terms of possible mudslides.

That's about all I understand. If you want to know more, check out this article which compares El Niño to a "'mini' global warming event." Something to think about as you ponder the potential effects of global warming.

Travelers to Peru during the coming months are advised to bring a rain coat.

*Which is why you see worse storms on the Western sides of the Pacific and Atlantic oceans.