Thursday, August 20, 2015

Bringing up baby

IT IS a long way from the western Pacific Ocean to the flooded streets of Buenos Aires where, this month, the city’s Good Samaritans have been distributing food and candles by kayak after some unseasonably heavy rain. But there is a link. Its name is El Niño.

El Niño (Spanish for “The Boy”) is a Pacific-wide phenomenon that has global consequences. A Niño happens when warm water that has accumulated on the west side of the Pacific floods eastward with the abatement of the westerly trade winds which penned it up. (The long, dark equatorial streak on the map above, which shows sea-surface temperatures for August 10th-16th, indicates this.) The trade winds, and their decrease or reversal, are part of a cycle called ENSO (El Niño Southern Oscillation—see article).

The consequences of this phase of ENSO include heavy rain in south-eastern South America, western North America and eastern Africa, and drought in Australia, India and Indonesia. Another consequence, around Christmastide, is the sudden...



from The Economist: Science and technology http://ift.tt/1HXVSTv

No comments:

Post a Comment