Wet season getting wetter and wetter

MANILA, Philippines—Rains and floods spawned by the storm-enhanced southwest monsoon are a sign our wet season is getting wetter, and monsoon episodes like this will only grow more frequent due to climate change, a state climatologist said Tuesday.

Rosalina de Guzman, chief of the climate data section of the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa), said extreme weather events were on the upswing in a trend that could only be attributed to climate change.

“In terms of intensity and frequency, we are seeing an increase in extreme weather events,” she said in an interview.

Pagasa climatologists analyzed daily data collected from weather stations throughout the country through the years 1951 to 2010 to determine the historical trend of intense rainfall incidents.

De Guzman said they focused only on historical highs of recorded rainfall from the traditional monsoon months of June to August, instead rainfall averages, in order to determine if there really was a rising trend in incidents.

“We wanted a scientific basis to conclude whether or not climate change was really happening,” she said.

“The results of the study showed that the frequency and intensity of rainfall in the monsoon months were going up,” De Guzman said.

Their conclusion, she said, was that “the wet season will become wetter and the dry season will become dryer.”

De Guzman said Filipinos should anticipate rainfall episodes “greater than 300 millimeters” like Tropical Storm “Ondoy” in 2009 and the torrential monsoon rains in August last year.

From Aug. 6 to 8 last year, Pagasa recorded 1,007.4 mm of rainfall during the monsoon. Ondoy on Sept. 25, 2009, dumped 455 millimeters of rain over Metro Manila in a 24-hour period.

Tropical Storm “Maring,” on the other hand, has dumped 300 mm of rain over a three-day period from Saturday to Monday.