Stephanie Nebehay, PlanetArk 2 Dec 09;
GENEVA - An El Nino weather pattern warming the Pacific Ocean and linked to drought in South Asia is likely to continue through the first quarter of 2010, the World Meteorological Organization (WMO) said on Tuesday.
The phenomenon, which began in June and intensified in October, has "implications for many climate patterns around the world over the next several months," the WMO said.
But a second year of El Nino conditions or rapid transition to a La Nina pattern -- its counterpart in which waters cool -- are considered "unlikely," according to the United Nations agency.
An El Nino, which means "little boy" in Spanish, is driven by an abnormal warming of the eastern Pacific Ocean. It can create havoc in weather patterns across the Asia-Pacific region, unleashing droughts in some places and heavy storms in others.
"El Nino conditions are very likely to continue at least through the remainder of 2009 and into the first quarter of 2010," the WMO said.
The last severe El Nino in 1998 killed more than 2,000 people and caused billions of dollars in damages to crops, infrastructure and mines in Australia and Asia.
Across the central and eastern Equatorial Pacific, sea surface temperatures were generally about 1 degree Celsius warmer than normal during the period of June-September, it said.
Average sea surface temperatures in the second half of October rose to around 1.5 degree Celsius warmer than normal, and most forecasting models expected this level will continue for November-February, according to the WMO.
The so-called "decay" phase of the El Nino back to near-neutral conditions across the tropical Pacific is considered likely during the March-May period, it said. Climate impacts in some regions typically continue through this phase.
El Nino is not the only factor that determines regional impacts, although it is "one of the most dominant," according to WMO climate scientist Rupa Kumar Kolli.
"There are climatological relationships between an El Nino event and some regional climatic patterns, such as an El Nino event being associated with weaker monsoons," Kolli told a news briefing.
"For example, we have seen that in South Asia, we have had a very weak summer monsoon which led to drought conditions."
But no two El Nino events are alike and there are other factors that actually compound its impacts, he said.
Australia's weather bureau said last week that weather indicators suggested a drought-bringing El Nino was maturing.
Equatorial Pacific Ocean temperatures remain at their highest levels since at least the El Nino event of 2002, it said, also pointing to models suggesting the phenomenon would continue into the first quarter of 2010.
(Editing by Sue Thomas)
