Until now, many people are confused as to which typhoon signal system is being utilized and enforced by PAG-ASA. Officially, it utilizes the Modified Public Storm Warning Signals with 4 Public Storm Warning Signals, as follows:
• PSWS#1 – for winds from 30-60 kph expected in the next 36 hours. Twigs and branches of small trees may be broken. Some banana plants may be tilted or downed. Some houses of very light materials (nipa and cogon) may be partially unroofed.
• PSWS#2 – winds from 60-100 kph in the next 24 hours. Some coconut trees may be tilted with few others broken. Few big trees may be uprooted. Many banana plants may be downed. Rice and corn may be adversely affected. Large number of nipa and cogon houses may be partially or totally unroofed. Some old galvanized iron roofings may be peeled off. In general, the winds may bring light to moderate damage to the exposed communities.
• PSWS#3 – winds from 100-185 kph in 18 hours. Many coconut trees may be broken or destroyed. Almost all banana plants may be downed and a large number of trees may be uprooted. Rice and corn crops may suffer heavy losses. Majority of all nipa and cogon houses may be unroofed or destroyed and there may be considerable damage to structures of light to medium construction. There may be widespread disruption of electrical power and communication services. In general, moderate to heavy damage may be experienced, particularly in the agricultural and industrial sectors.
• PSWS#4 – winds above 185 kph in 12 hours. Coconut plantation may suffer extensive damage. Many large trees may be uprooted. Rice and corn plantation may suffer severe losses. Most residential and institutional buildings of mixed construction may be severely damaged. Electrical power distribution and communication services may be severely disrupted. In the overall, damage to affected communities can be very heavy.
On the other hand, the internationally used Saffir-Simpson Scale for classifying typhoons or hurricanes, has the following categories:
• Category 1 – Minimal, 119-153 kph. Some damage is expected, with most of it limited to shrubbery, unanchored houses and items. Some minor flooding will cause pier damage.
• Category 2 -- Moderate, 154-177 kph. Considerable damage can be expected to shrubbery and some trees may be blown down; there will be damage to mobile homes, signs, roofs, windows and doors. Small craft may be torn from moorings and marinas will probably flood. Some low-lying areas and shoreline residences should be evacuated.
• Category 3 -- Extensive, 178-209 kph. Large trees and most signs may be blown down; there may be structural damage to small buildings; mobile homes will be destroyed. Serious flooding will occur at the coast, with severe damage to shoreline structures and flooding up to eight miles (13 km) inland at elevations of five feet (1.5 m) or less.
• Category 4 -- Extreme, 210-250 kph. Expect trees, signs and traffic lights to be blown down, and extensive damage done to roofs, windows and doors. Mobile homes will be completely destroyed. Beaches will be eroded and there will be flooding as far as 6 miles (9.5 km) inland for anything under 10 feet (3 m) above sea level. Anyone staying within 500 yards (457 m) of shore will be evacuated, as will all single-story residences within 2 miles (4 km) of shore.
• Category 5 -- Catastrophic, 251+ kph. Trees, signs, traffic lights will be blown down.
There will be extensive damage to buildings and major damage to lower floors of structures less than 15 feet (4.5 m) above sea level within 500 yards (457 m) of shore. Massive evacuation of residential areas 5-10 miles (8-16 km) from shore will be required.
Comparing the two, it is obvious that Saffir-Simpson has a more precise system for having smaller wind-speed differentials between categories. Although more cumbersome with its 5 categories, it allows more accurate determination of effects on the human environment. Its major disadvantage is the absence of a category for wind speeds below 119 kph. It was obviously designed for highly developed countries with more durable infrastructure.
The PAG-ASA system is clearly designed to warn people in agricultural areas. Unfortunately, it does not provide a graphic warning for urban dwellers. In this Post-Milenyo era, we hope this can be amended. Example: Oversized and medium-sized billboards toppling over vehicles and across major roads. (Sorry, can’t resist that one.)
Furthermore, using the two systems to analyze the average wind speed of Milenyo, it seems clear that typhoon Milenyo had sustained wind velocities of no less than 150 kph and not the reported 120 or 130 kph. In short, Milenyo was both a PSWS#3 and, at least, a Category 2 typhoon. Comparing it with Typhoon Trining (Ruth) which hit
(This gustiness thing is one particularly intriguing phenomenon. My friend and I noticed a portion of the metal-sheet ceiling underneath LRT 1 in Avenida twisted out of place. He said, thieves did it. I noticed though that that small portion happened to be right along a thru-street (Raon, I think). The wind had accelerated through the buildings along that alley and produced a negative pressure within the ceiling, sucking it out of connection and exposing the electrical wires. That’s exactly how some well-attached roofs are sucked out. The lesson? Wind speed can be positive and negative. It may push or pull out.)
Justifying its system of averaging expected wind velocities over a shorter period, v.v. the longer period used by other countries, PAG-ASA’s final lower average has resulted in underestimating the speeds and the effects of Milenyo. A careless error if I may say so. In such cases, a “worse”-case scenario is better. That is, erring on the side of caution is much better when lives and properties are at stake. However, it is not that way with people used to disasters; either they tend to take an idle optimistic view or a fatal fatalistic one. We’ll make it through somehow! Or, what can we do?
Finally, cleansing works for our own good. It takes away the weak branch or tree that has failed to give fruit or serve its purpose except as firewood or fertilizer. It takes away old ways that will and can no longer work to improve our way of doing things. Funny how many people fight to retain such failed ways by undoing the works and the lessons nature and God hand us.
Cleansing, like fasting and praying, takes away the poison within us and around us. We don’t just suffer a typhoon, a disaster or even a war (God forbid). We don’t become less from a painful catharsis. We become what we should be. The world becomes what we could make of it. Society becomes a home people by cleansed – no, purified and refreshed – people.
(Top Photo: Traffic along EDSA as seen from the Ayala MRT Station. Photo Above: At a construction site in Makati, a pheumatic hammer breaks down the old to build up the new.)
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