El Nino odds said to rise above even

Reuters 3 Jun 09;

MELBOURNE (Reuters) - Australian farmers stand a greater-than-even chance of being hit by a drought-inducing weather pattern known as El Nino, the country's official weather forecaster said on Wednesday.

The Bureau of Meteorology said that if recent trends in Pacific climate patterns held up, there was an above-50 percent chance an El Nino event would be established by July. That is more than double the normal risk of an El Nino in any year.

"This view is supported by several computer forecasts of El Nino, which have firmed in their predictions of an event in 2009," David Jones, head of climate analysis at the bureau's National Climate Center, said in a statement.

Last month, the bureau had put the odds at above 20 percent.

U.S. forecasters at Colorado State University said on Tuesday there was "a slightly greater chance of a weak El Nino developing this summer/fall than there was in early April."

Australia is the world's fourth-largest wheat exporter. The possibility of an El Nino could reduce estimates for the next crop, which is now being sown.

"If it plays out that we do have a drier season again, particularly through spring, then for some farmers it will be diabolical because they have had three or four seasons in a row...of bad, failed crops," said Gavin Warburton, crop analyst at Australian Crop Forecasters.

However, he said it was too early to adjust forecasts, given there was no certainty that El Nino would occur. Even if it did, the extent of the impact on rainfall could vary, he added.

Current estimates for the crop range from 21 million to 23 million metric tons, little changed from the 21.4 million metric tons harvested in 2008/09, which was the best crop in four years following drought-breaking rains in some parts of the country.

El Nino means "little boy" in Spanish and it creates havoc in weather patterns across the Asia-Pacific region.

Scientists have linked El Nino events in the Pacific Ocean with Australian droughts. El Nino occurs when the eastern Pacific Ocean heats up, with warmer, moist weather moving toward the east, leaving drier weather in the western Pacific and Australia.

The most devastating El Nino was in 1997/98 when it caused drought in Australia and Indonesia and floods in Peru and Ecuador.

The bureau said surface temperatures across the equatorial Pacific had risen by about 0.8 degrees Celsius since the start of April to 0.5 degrees Celsius above average. The El Nino threshold is 0.8 degrees Celsius above average.

"It is still possible that the recent trends may stall without the El Nino thresholds being reached," the bureau said.

(Reporting by Simone Giuliani; Editing by Mark Bendeich)