By David Fogarty
SINGAPORE, Aug 21 (Reuters) - An emerging El Nino weather pattern is likely to have only a modest impact on crops and mining in Australia and could benefit sugar cane growers in Queensland, a senior forecaster said.
Drier conditions have already settled in over much of the country, with August rainfall to date only about 20 percent of normal, said Andrew Watkins, manager of climate prediction at Australia's Bureau of Meteorology's National Climate Centre.
But full-blown drought was not in the forecast for the coming months, he said.
Anxiety has been growing about the impacts of the developing El Nino in the Pacific Ocean.
Drought in other parts of the globe has sent food prices soaring and the worry is El Nino will hurt more crops and fuel even higher price rises. Australia is the world's number two wheat exporter and the third largest sugar exporter.
"The odds are there for drier than normal conditions - eastern Australia particularly and northern Australia as well later on when it comes to the monsoon," Watkins said in an interview from Melbourne.
El Nino is a periodic warming of the eastern tropical Pacific Ocean and typically weakens or even reverses the trade winds that normally blow to the west. The winds are a key driver for rainy weather in Southeast Asia and parts of Australia.
Miners, oil and gas firms in the U.S Gulf and insurers are also following the event closely because El Nino can trigger global weather chaos - typically drought in Australia, Southeast Asia and India and floods and storms in parts of South and North America. Severe El Ninos in the past have killed thousands of people and caused billions in damage.
Watkins said El Ninos typically means fewer cyclones forming around northern Australia from November to April. That means coal, iron ore and bauxite miners, as well as oil and gas rigs and liquefied natural gas production plants will likely face fewer disruptions, a marked change from 2010-12.
El Nino's polar opposite, La Nina, typically brings floods and more storms to Australia and Southeast Asia. Back-to-back La Nina events in 2010-12 flooded coal mines in Queensland, shutting some for months and costing billions in lost production.
SAME BUT DIFFERENT
Japan this month declared a weak El Nino was under way but Australia and the United States have been more cautious because it has yet to have a significant impact on atmospheric circulation patterns in the Pacific.
"I think it's going to probably bubble along close to the threshold to some degree - it may well tease us for a little while longer," Watkins said.
For large parts of Australia's main agricultural zones, soil moisture remains average to above average, providing a buffer for drier months. The wheat-growing areas of western Victoria state and the southwest of Western Australia were the exception, he said, after recent very dry weather in those regions.
Drier weather after recent rains will help the sugar cane harvest in Queensland, he added.
Globally, computer models used by weather agencies also show that, on average, a mild El Nino will form.
The problem is no two El Ninos are the same. A 1997-98 event, one of the strongest on record, had only a weak impact on crops in Australia but a severe impact on Southeast Asia.
Yet weak to moderate El Ninos of 2002-03 and 2006-07 caused widespread crop losses in Australia.
The 2002-03 El Nino slashed the wheat crop to 10.1 million tonnes from 24.3 million in 2001-02, according to the Australian Bureau of Agricultural and Resource Economics and Sciences.
That is because in some El Ninos, the warming shifts more towards the central Pacific. In the past, such events tended to trigger drier conditions in Australia and Southeast Asia.
The current emerging event is also showing signs of similar ocean warming in the central tropical Pacific, Watkins said, adding there was a trend towards more of this type of El Nino.
"So this is one to watch. The science isn't settled but there is something to suggest they have a little bit more impact than if they were purely an eastern Pacific event." (Editing by Robert Birsel)