The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) warned about the possibility of La Niña occuring in the second half of this year, in the wake of the waning El Niño.
The Philippines should brace for an extremely wet season as the La Niña is expected to bring more typhoons than usual into the Philippines.
The La Niña is a climate pattern associated with the abnormal cooling of surface oceans along the tropical west coast of South America and the rise in sea temperature over the tropical portion of the Pacific Ocean just east of the Philippines.
The pattern is the exact opposite of what happens during El Niño, when the waters surrounding the country are cooler than usual, resulting in fewer rains.
Both phenomena are part of the so-called El Niño Southern Oscillation or ENSO.
According to GMA resident meteorogist Nathaniel “Mang Tani” Cruz, above-normal ocean temperatures result in more precipitation.
“Dahil you have a warmer sea temperature, you have more moisture, more evaporation, more condensation, so we should expect na mas madalas mas maulan dito sa atin because of La Niña,” he said.
He added that the interaction of the easterly winds with the Southwest Monsoon this May may lead to the formation of typhoons.
“Dito sa may Philippine Sea, malakas ‘yung easterlies mo and then ‘yung opposing wind, which is yung southwest monsoon, nagiging mas madalas ngayon yung pagkakaroon ng bagyo dahil mayroon ka nang opposing wind na puwedeng pagsimulan ng circulation na puwedeng maging bagyo,” Mang Tani said.
He added that, under normal conditions, 19-20 typhoons may enter the Philippine Area of Responsibility (PAR) in a year, but only half may be expected to cross the country.
However, PAGASA already projects 7-12 typhoons entering the PAR in the period of May to October alone. The La Niña may bring in more in the latter part of the year.
“Ngayon pinag-uusapan natin ang La Niña and yet we are still feeling the effects of El Niño at this very moment. Mangyayari ito hindi sa mga susunod na buwan kung hindi sa later part of the year,” he indicated.
PAGASA likewise expects drought to prevail in some parts of the country until September. https://pubfiles.pagasa.dost.gov.ph/climps/climateforum/climateoutlook.pdf
Mang Tani said that the La Niña could last for several months extending through to next year, and that Visayas and Mindanao should brace for intense weather.
“Pagdating ng La Niña, sobra-sobra namang ulan, parehong extreme, probably hanggang next year. ‘Yung mga tiga-Visayas and Mindanao, posibleng malakas ang ulan diyan kung malakas ang event na ito,” he said.
Mang Tani said that La Niña doesn't always come after El Niño. He said it still depends on how strong the event is before it could be predicted if the other event will follow.
The Philippines last experienced La Niña in 2010 to 2011.
Mang Tani added that La Niña affects other countries differently: the United States, for example, may experience drier and warmer weather than usual. — TJD, GMA News