What Is El Niño and How Does it Affect Weather Around the World?

Here’s what can happen when the surface of the equatorial Pacific gets just a little warmer: Thousands of people die as the weather changes from India to Florida. Some economies lose billions of dollars; others enjoy respite from weather-related losses. Prices of commodities such as coffee and cocoa jolt skyward. Then when the waters cool, patterns shift, with areas previously spared often experiencing calamitous hurricanes, floods or drought, and others getting a break from such buffeting forces. The whole cycle is known as El Niño-Southern Oscillation. It is made up of El Niño, the Pacific’s warm phase; La Niña, the cold side; and a neutral phase in between. The US declared that the whole thing kicked off again in June, and Australia, which uses different criteria, concurred on Sept. 19.