El Nino

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http://www.timesonline.co.uk/tol/news/worl...icle6695339.ece

El Niño, the warming of the Pacific Ocean that creates chaos in global weather patterns, is on its way back, threatening droughts, floods, crop failure and social unrest.

According to scientists at America’s National Oceanic and Atmospheric Administration (NOAA), a new bout of El Niño is under way as the surface of tropical waters across the eastern Pacific has warmed roughly 1C (1.8F) above normal and is still rising.

Further down, some 150 meters (500ft) below the surface, the waters are heating up — by around 4C (7.2F).

These indications have been emerging for about the past month from satellite pictures and an array of robotic buoys strung out across the Pacific. “The persistently warm sea temperatures are important indicators of an El Niño,†Mike Halpert, of NOAA’s Climate Prediction Centre, said.

function slideshowPopUp(url) { pictureGalleryPopupPic(url); return false; } “We’re also seeing a link between the ocean and the atmosphere, with Indonesia tending to dry out as tropical rainfall shifts towards the international dateline in mid-Pacific.â€

The implications are severe, not just for climate but for the effects on food, water supplies and other commodities. Australia, still recovering from its worst drought in a century, will be hit again if the rains fail to nourish its wheat belt. Indonesia is one of the world’s biggest producers of palm oil — a basic source of income for many of its poor — and a drought would hit this commodity hard.

Farming in India is already suffering from an abnormal monsoon, which scientists think could be related to the emerging El Niño.

The rains arrived early but stalled. They picked up speed again only last week and covered the whole of the country, although rainfall is far lower than normal. There are fears that, if the rains do not improve, water shortages will kill crops and lead to soaring food prices.

Shortages and food prices caused riots all over the world in 2008, from western Africa to Mexico, Uzbekistan, Haiti and Egypt, as well as consumer protests in Europe and panic in food-importing countries. Rice-producing nations were urged to stop hoarding supplies as stocks fell to their lowest levels for 30 years.

The emerging El Niño is expected to continue strengthening over the next few months and reach a peak during the northern hemisphere’s winter. However, every bout of El Niño is different and much depends on the extent to which the Pacific warms up. At present forecasters say that it is too early to assess this El Niño — the NOAA’s meteorologists expect to have a clearer picture in September or October — but early signs suggest that it could become a moderate-to-strong episode.

El Niños are still something of a mystery. They recur every few years and vary hugely in strength but no one entirely understands why. When a severe one does strike it unhinges weather patterns across the Pacific and beyond, leading to drought in some areas and heavy rains in others, such as the western coast of South America.

In the last severe episode in 1997-98 torrential rains pulverised California, heatwaves swept across Australia and Brazil, forest fires blanketed Indonesia, eastern Africa was flooded while southern Africa withered under drought, and floods and storms caused billions of dollars’ damage to crops and buildings.

That episode was so strong that it helped to break the record for the world’s highest average temperature for the year, which has not been broken since. The turmoil in the global climate caused havoc with food prices as staple crops such as wheat, rice and sugar were hit hard.

There are, however, some benefits to El Niño, especially in the US. It tends to kill off hurricanes in the Atlantic, bring welcome rainfall to the arid southwest, a milder winter across the north, and a reduced risk of wildfires in Florida. Sometimes El Niño — Spanish for “little boyâ€, a reference to Jesus as its effects were said to be most pronounced around Christmas — has even helped to change history.

About 1,500 years ago the Moche civilisation of Peru suffered severe El Niño spells that are thought to have led to its downfall.

A severe El Niño in 1787-88 may have set off the atrocious weather in France that led to crop failures, soaring food prices and ultimately the French Revolution.

In 1520 El Niño is thought to have given the explorer Ferdinand Magellan unusually plain sailing over calm Pacific seas as he sailed from South America to the Philippines, where he was killed in a battle with natives.

There is even a positive aspect for Australians: a recent study has linked El Niño to increased chance of an Australia-in-Australia Ashes victory. Records from 1882 to 2007 show that the tendency for dry wickets in El Niño years favours their fast bowlers.