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LONDON - A combination of global warming and the El Nino weather system is set to make 2007 the warmest year on record.
The forecast is for extreme global weather patterns which could bring drought to Indonesia and leave California under a deluge.
The warning, from Professor Phil Jones, director of the climatic research unit at the University of East Anglia, was one of four sobering predictions from senior scientists and forecasters that this will be a crucial year for determining the response to and effects of global warming.
Professor Jones said the long-term trend of global warming was set to be exacerbated by the arrival of El Nino, the weather phenomenon caused by above-average sea temperatures in the Pacific.
The resulting extreme weather worldwide would make 2007 warmer than 1998, the hottest year on record. Globally, 19 of the hottest 20 years on record have occurred since 1980.
Professor Jones said: "El Nino makes the world warmer and we already have a warming trend that is increasing global temperatures by one to two tenths of a degree celsius per decade.
"Together, they should make 2007 warmer than last year and it may even make the next 12 months the warmest year on record."
The warning of the escalating impact of global warming was echoed by Jim Hansen, the American scientist who was one of the first to warn of climate change in 1988.
Dr Hansen predicted that global warming would run out of control and change the planet forever unless rapid action was taken to reverse the rise in carbon emissions.
"We just cannot burn all the fossil fuels in the ground. If we do, we will end up with a different planet," he said. "I mean a planet with no ice in the Arctic, and ... sea level rises and the extinction of species."
His call for action is shared by Sir David King, the British Government's chief scientific adviser, who said that last year had shown that the "discussion is now over" on whether climate change was happening.
Sir David said progress had been made in the past year but it was essential that a global agreement on emissions be struck quickly.
"We need to remember: action is affordable - inaction is not."
The demands came as the World Meteorological Organisation (the United Nations agency that deals with climate prediction) issued a warning that El Nino was already established over the Pacific.
It is set to bring extreme weather from the Americas and southeast Asia to the Horn of Africa for at least the first four months of the year.
El Nino, or "the Christ child" because it is usually noticed around Christmas, is a weather pattern occurring every to two to seven years generated by above-average sea temperatures. Warm water off North and South America causes trade winds to die and brings increased rainfall and storms to the Americas while drought hits Australia and the western Pacific. The last severe El Nino, in 1997-1998, caused 2000 deaths and left a large bill for damages.
The UN agency said its latest readings showed that a "moderate" El Nino, with sea temperatures 1.5C above average was taking place. It could develop into an extreme weather pattern lasting up to 18 months.
It noted that the weather pattern was already having "early and intense" effects, including drought in Australia and dramatically warm seas in the Indian Ocean, which could affect the monsoons.
It warned the El Nino could also bring extreme rainfall to parts of eastern Africa, which were last year hit by a cycle of drought and flooding.
Although the weather phenomenon is separate from global warming, scientists know that the two combined can lead to an exceptionally warm year.
In 1998, during the last El Nino, the average worldwide temperature was 0.71C above the 30-year average.
The average temperature in Britain last year beat the previous two joint hottest years, 1999 and 1990, by 0.21C, a dramatic difference in meteorological terms.
Last year would also have been even hotter were it not for the effects of La Nina, the "twin" of El Nino, which is caused by below-average sea temperatures.
- INDEPENDENT
