The World Meteorological Organization (WMO) on Monday warned against possible climate extremes, as moderate to strong La Nina conditions are likely to continue into at least the first quarter of 2011.
In its latest update of the current La Nina event, the WMO said this La Nina, following the dissipation of the latest El Nino in April 2010, are "now well established in the equatorial Pacific."
According to WMO, the phenomenon can be observed from the abnormal ocean temperature and ocean-atmosphere interaction registered in the central and eastern equatorial Pacific.
The surface temperature of the vast span of ocean is 1.5 degrees Celsius below average, and the subsurface water temperature is 2 to 6 degrees Celsius below average.
Given the current situation, the WMO expected the La Nina conditions to further strengthen in the next four to six month period.
La Nina is an ocean-atmosphere phenomenon that often occurs in couple with El Nino. The two events are often regarded collectively as El Nino-Southern Oscillation climate pattern. A La Nina is often preceded by a strong El Nino.
When La Nina occurs, the sea surface temperature over the central and eastern equatorial Pacific will be lower than normal, causing major climate fluctuations around the globe and possible catastrophic weather events in some regions.
The last La Nina was a moderate one, which started in mid 2007 and lasted till early 2009.