EDITORIAL — Flawed warning system

One problem stands out amid the devastation caused by monsoon rains enhanced by Typhoon Carina: the nation was caught unprepared because the dangers posed by monsoon-induced cataclysmic rainfall was not emphasized enough.

People went to work as if it was a normal rainy day last Wednesday and even the oil tanker Terra Nova was cleared to leave the port of Limay, Bataan for Iloilo on Thursday because there was no storm warning signal over Metro Manila and neighboring areas. Instead Signal No. 2 was hoisted over much of Northern Luzon by the Philippine Atmospheric, Geophysical and Astronomical Services Administration. PAGASA said Carina would not even make landfall in the Philippines.

PAGASA bases storm signals on wind speed. Class suspensions are based on such storm signals. Carina’s winds would intensify only as it exited the Philippine area of responsibility and headed for Taiwan, where its strength merited classification as a super typhoon.

The country has enough Doppler radars to assess the expected amount of rainfall during weather disturbances. As Carina passed through the Philippine area of responsibility, rainfall warnings were issued regularly through blaring alerts on smartphones by the National Disaster Risk Reduction and Management Council. The warnings, however, were issued in real time – meaning that by the time people received the alerts for red, orange or yellow rainfall, they were already stuck with their vehicles in destructive floods, or stranded while waiting for rides in flooded streets. People who went to work and were later sent home had to scramble to find their relatives who were forced to evacuate, or who were stranded in inundated houses.

As in Tropical Storm Ondoy in 2009, many people were surprised by the rapid rise of floodwaters, leaving them with no time to bring electric appliances and furniture to safety, or to make emergency preparations for food and hygiene. Residents also complained that it took an unusually long time for the floodwaters to recede.

The experts warned that Carina would enhance the southwest monsoon, which could bring heavy rain. Disaster officials need to use a word far less benign than “enhance” to convey an urgent warning about heavy rainfall that could spawn apocalyptic flooding. The warning must be issued strongly and clearly long before the rain starts pouring. And the public must be sufficiently informed that such a warning can be as dire as a strong storm signal.

This week’s devastating floods have been aggravated by blocked waterways particularly in Bulacan and a damaged floodgate in the case of northern Metro Manila. The blocked waterways pose a tough challenge, but preparedness can be improved through a better warning system that factors in both wind speed and the projected amount of rainfall.