By Catherine J. Teves
MANILA, July 26 — The Philippines will likely experience, beginning late this year, another round of the drought-inducing El Niño phenomenon.
Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said forecasting models show the Pacific Ocean's sea surface temperature is warming already — a characteristic observed prior to full development of El Niño.
"There's a big probability El Niño will develop this year," PAGASA Administrator Dr. Nathaniel Servando said Thursday during a climate forum in Metro Manila.
El Niño periods are characterized by deficit in rainfall.
PAGASA reported data show warming in the Pacific commenced in April this year following the 2011-2012 episode of the wet La Niña phenomenon which is El Niño's opposite.
Climate Prediction Center's modeling as of late July 2012 indicate probable occurrence of another El Niño episode beginning this year, PAGASA reported.
Modeling of Australia's Bureau of Meteorology as of July 17 this year also show conditions in tropical Pacific are nearing the El Niño threshold, PAGASA continued.
Those and other forecasting models indicate some 70 percent probability of El Niño's return in 2012, PAGASA noted.
The Philippines' last El Niño episode occurred during the 2009-2010 period.
PAGASA declares full-blown El Niño after observing five consecutive months of Pacific sea surface temperature anomaly above 0.5 degrees Centigrade.
Such anomaly represents deviation from the Pacific's normal sea surface temperature which varies due to several factors, PAGASA noted.
During the forum, PAGASA also reported it forecasts rise in temperature as well as below-normal rainfall in different parts of the country during late 2012.
Between nine to 14 tropical cyclones are likely to enter/develop within the Philippine Area of Responsibility during the August-December 2012 period, PAGASA added.
El Niño/La Niña-Southern Oscillation, ENSO or jujst plain El Nino, is a quasiperiodic climate pattern that occurs across the tropical Pacific Ocean roughly every five years.
The Southern Oscillation refers to variations in the temperature of the surface of the tropical eastern Pacific Ocean (warming and cooling known as El Niño and La Niña respectively) and in air surface pressure in the tropical western Pacific.
The two variations are coupled: the warm oceanic phase, El Niño, accompanies high air surface pressure in the western Pacific, while the cold phase, La Niña, accompanies low air surface pressure in the eastern Pacific.
Mechanisms that cause the oscillation remain under study.
The extremes of this climate pattern's oscillations, El Niño and La Niña, cause extreme weather (such as floods and droughts) in many regions of the world.
Developing countries dependent upon agriculture and fishing, particularly those bordering the Pacific Ocean, are the most affected. (PNA)