What you need to know about El Niño

The world is being told to brace for another El Niño event this year. Here's what you need to know:

1. El Niño relates to feedbacks between the atmosphere and ocean that occur every two to seven years.

2. An El Niño event occurs when the prevailing trade winds that circulate over surface waters in the tropical Pacific start to weaken.

3. This allows warm waters of the western Pacific to wash back eastward, dragging precipitation with it.

4. The name El Niño is believed to have been coined in the 19th century by Peruvian fishermen. It is Spanish for boy, in reference to the infant Jesus Christ.

5. The El Niño of 1997/8 was the worst in modern history, causing deadly mudslides in South America, a crippling drought in south-east Asia and extreme weather almost everywhere else.

6. This year the fallout could lead to heavy snowfall in Britain, and India and Australia are likely to be hit the hardest.

7 . It could lead to a weak monsoon in India, which has raised fears of low crop production and rising food prices.

8. The phenomenon also precipitates heavier rainfall in the South American and eastern Pacific nations, raising the prospect of floods and landslides.

9. El Niño does not spell bad news for everyone: the event is expected to bring much-needed rain to the American west, which has been subjected to a severe drought in recent months.

More: El Niño will strike this year