As monster El Niño looms, the world rushes to get ready

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The world is preparing for a massive El Niño that could be the strongest since 1998. So far it has led to the deaths of an estimated 20,000 people and caused almost $100 billion of damage.

El Niño emerges when winds blowing west across the Pacific weaken, and warm water spreads out east towards South America, dragging rainfall with it. As a result, chunks of Asia and Australia dry out, and rain is dumped on much of the Americas. The effects are felt further afield too, especially in Africa. El Niños are irregular, developing at intervals of two to seven years and lasting between nine months and two years.

The El Niño will intensify in the coming months and probably peak around February. The rains are yet to hit Africa and South America; marine impacts such as coral bleaching are expected to begin around December.