THE Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) yesterday warned the public of the possibility of another weather disturbance hitting the country before the end of the year.
Pagasa Mactan Chief Al Quiblat said this is because December has an average of one to two tropical cyclones a year.
Quiblat clarified that it is “misleading” for media to report a weather disturbance as a typhoon, unless it has strength from 118 kilometers per hour (kph) and above.
“Tropical cyclone is the generic name for cyclonic system, which has three types or categories, such as tropical depression, which has 30 to 60 kph(winds); tropical storm, which has 60 to less than 118 kph; and typhoon, which has 118 kph and above,” said Quiblat.
He said that as far as the Philippines is concerned, there is no such thing as a super typhoon. But there is a proposal in their Central Office in Manila to declare a super typhoon.
Quiblat said the fact that the country faces the Pacific Ocean helps explain why the country has an average of 20 tropical cyclones every year.
Quiblat said that if the tropical cyclones will happen in November and December, there is a 60 to 70 percent chance that these will hit the Visayas. He cited Nitang in 1984, Ruping in 1990 and Yolanda in 2013.
“Cebu has an average of one typhoon a year,” said Quiblat.
He said that the factors for a tropical cyclone are: the temperature of the sea beyond 26 degrees Celsius and the Coriolis force or the force caused by the earth’s rotation.
He said that if the temperature of the sea produces enough amount of latent heat (“hinungaw sa dagat”) or water vapor, that can develop into a cyclone.
Quiblat described Coriolis force as similar to a spinning top, which produces wind while in rotation.
Quiblat said Visayas and Luzon experience more tropical cyclones compared to Mindanao because these two areas are near the equator.
“If you are at the center of the earth or equator, there is less force or less circulation of strong wind because of less Coriolis force,” said Quiblat, adding this is also the reason people in Mindanao will experience tropical cyclones only once in every 30 years.
Quiblat, however, said that because of climate change, Mindanao was hit by typhoon Sendong in December 2012 and typhoon Pablo in October 2013.