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A patch of ocean near Greenland has cooled by about 1°C over the past few decades (Getty Stock Images)
How does an El Niño year happen?
Strap in, folks. It’s time for some science.
It all starts with something called trade winds, which are permanent winds around the equator which usually blow from east to west. So in the equatorial Pacific, they blow from the Americas towards Australia and New Zealand.
As the wind blows the water east, it is warmed by the sun, so by the time it gets to the other side of the Pacific, the warm water causes hot air to rise, leading to warm, wet and unsettled weather. Meanwhile, colder water from deeper in the ocean rises in the east to replace the water blown west.
But during El Niño years, this gets disrupted.