My Community, Our Earth Geographic Learning for Sustainable Development Philippine Science High School Southern Mindanao Campus
Exposed Visayas and The Potential Disasters That Threaten Its Localities
Proponents of the Project
Amolato, Rochie D.
Arpas, Matthew Karl David P.
Grecia, Claire F.
Sillada, Mariz Stella S.
Tonzo, Anjo John M.
Green Science Camp Project
Aurantiacis Aqua Dux
Subcamp Advisers
Engr. Cromwell Castillo
Ms. Ferly Caga
Research Adviser:
Michael A. Casas
I. Map with Description
Figure 1. Map of Cities Frequently Affected by Typhoons in the Visayas Region
Several cities in the Visayas are easily affected by typhoons. The map is a representation of the vulnerability of Visayas to typhoons, which enables us to set out certain points to focus on the typhoon frequency in the Visayas and its current vulnerability percentage.
II. Project Summary The Visayas region is made of multiple islands found west of the Pacific Ocean. The region is continually hit by storms and typhoons. People tend to suffer much from these storms, this is why the researchers decided to evaluate how susceptible the Visayas is to these said calamities. Data were obtained from the internet and were interpreted after. Assessment of the region’s vulnerability shows that it is commonly hit by tropical typhoons with winds that reach up to 120 kph, followed by tropical cyclones, tropical storms, and super typhoons. With these storms “nipa” houses can be easily blown off, while tough cement houses can still stand up. Damages done by these cyclones may reach up to 0.5 % of the country’s gross domestic product (GDP), with agricultural products, properties and infrastructures sustaining considerable damage.
III. Objectives 1) to determine the vulnerability of Visayas to tropical typhoons; and 2) to identify which island in the Visayas in most vulnerable to tropical typhoons.
IV. Project Methods The researchers retrieved data on incidence of tropical typhoons in the Visayas from the internet particularly the National Statistics Office, World Meteorological Organization, and Philippine Atmospheric, Geophysical and Astronomical
V. Findings and Results
1) Typhoon vulnerability of Visayas, Philippines-Geopolitical Setting
1.1) Geographical The Visayas is a major group of islands in the Philippines which consists of Bohol, Cebu, Leyte, Masbate, Negros, Panay, and Samar, and hundreds more of small individual islets. The islands here are generally mountainous. Their shores have large and densely populated coastal areas also known for diving spots and white sand beaches including Boracay. The Visayas, being found west of the Pacific Ocean, is visited yearly by twenty strong storms and typhoons, which damages up to 0.5% of its gross domestic product (GDP).
1.2) Economical
Table 1. Population of Visayas on 1990, 2000 and 2010 Region Total population Population Growth Rate 1-May- 1-May- 1-May- 1990- 2000- 1990- 90 00 10 2000 2010 2010 Region VI – Western 5,393,333 6,211,038 7,102,438 1.42 1.35 1.38 Visayas Region VII – Central 4,594,124 5,706,953 6,800,18 2.19 1.77 1.98 Visayas Region VIII – 3,054,490 3,610,355 4,101,322 1.68 1.28 1.48 Eastern Visayas
The Visayas has a rich volcanic soil which is ideal for growing coconuts, cotton, sugarcane, rice and tobacco. Inhabitants also live mainly by fishing, forestry, mining, and production of weaved goods. Tourism is also one major industry in which the Visayan economy is greatly dependent. As seen in Table 1, the region has an increasing population with central Visayas having the greatest population growth, suggesting a large migration in the said area. This increasing population is one of the reasons why vulnerability analysis has to be done, so eventually fewer citizens need to suffer from the havoc wreaked by typhoons.
2)Meteorological/Climatological Setting
2.1) Climate Types
Table 2. Climate data for Cebu Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year Average 29.9 30.2 31.2 32.3 33.0 32.1 31.7 31.9 31.7 31.6 31.2 30.3 31.43 high °C (85.8) (86.4) (88.2) (90.1) (91.4) (89.8) (89.1) (89.4) (89.1) (88.9) (88.2) (86.5) (88.57) (°F) Daily 26.8 27.0 27.8 28.8 29.4 28.7 28.3 28.4 28.3 28.1 27.9 27.3 28.07 mean (80.2) (80.6) (82.0) (83.8) (84.9) (83.7) (82.9) (83.1) (82.9) (82.6) (82.2) (81.1) (82.52) °C (°F) Average 23.8 23.7 24.4 25.4 25.9 25.3 24.9 25.0 24.8 24.7 24.7 24.2 24.73 low °C (74.8) (74.7) (75.9) (77.7) (78.6) (77.5) (76.8) (77.0) (76.6) (76.5) (76.5) (75.6) (76.52) (°F) Rainfall 78.1 62.3 41.5 29.1 54.8 149.9 157.0 136.5 167.3 148.4 131.4 103.8 1,260.1 mm Table 3. Climate(3.075) data(2.453) for Borongan(1.634) (1.146), Eastern (2.157) Samar (5.902) (6.181) (5.374) (6.587) (5.843) (5.173) (4.087) (49.61) (inches) Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year Record high °C 33 31 33 32 35 36 35 37 35 35 34 33 37 (°F) (91) (88) (91) (90) (95) (97) (95) (99) (95) (95) (93) (91) (99) Average high °C 28 28 29 31 31 32 32 32 32 31 30 30 30.5 (°F) (82) (82) (84) (88) (88) (90) (90) (90) (90) (88) (86) (86) (86.9) Average low °C 21 21 21 22 23 24 24 24 24 24 23 22 22.8 (°F) (70) (70) (70) (72) (73) (75) (75) (75) (75) (75) (73) (72) (73.0) Record low °C 14 14 16 16 17 20 22 21 21 21 19 17 14 (°F) (57) (57) (61) (61) (63) (68) (72) (70) (70) (70) (66) (63) (57) Precipitation mm 640 430 320 260 240 230 180 140 180 330 530 640 4,120 (inches) (25.2) (16.93) (12.6) (10.24) (9.45) (9.06) (7.09) (5.51) (7.09) (12.99) (20.87) (25.2) (162.2)
There are four major types of climate in the Philippines. These are:
§ Type I. Two pronounced season: dry from November to April and wet during the rest of the year. § Type II. No dry season with a pronounced rainfall from November to January. § Type III. Seasons are not very pronounced, relatively dry from November to April, and wet during the rest of the year. § Type IV. Rainfall is more or less evenly distributed throughout the year.
Borongan, eastern Samar, a part of eastern Visayas, has a type II climate (refer to Table 3). It can be seen to have not much difference in its temperatures all throughout the year. Storms too, can be one of the reasons for this, which contribute to the rainfall yearly. Cebu, a part of central Visayas, has more of a two sided climate - one with low rainfall and one with a high rainfall, thus classifying it as a type III. This type III climate indicates that typhoons usually occur and hit the area from May to October.
3) Tropical Cyclone Hazard assessment
Table 4. Financial damage of selected storms that hit Visayas Name Date Occurred Deaths Damage(Financial PHP) Location September 30- Pepeng (WMO 465 (47 Eastern Visayas October 10, 27.3 billion name: Parma) missing) and Luzon 2009 Frank(WMO name: June 18-23, 557 (87 13.5 billion Luzon and Visayas Fengshen) 2008 missing) Loleng (WMO October 15-24, 303 (29 6.7 billion Visayas and Luzon name: Babs) 1998 missing) Milenyo (WMO September 25- 228 6.4 billion Luzon and Visayas name: Xangsane) 29, 2006 November 28- Reming (WMO 734 (762 December 2, 5.8 billion Luzon and Visayas name: Durian) missing) 2006 Eastern Visayas Juaning (WMO July 24-31, 77 4.44 billion and Northern name: Nock-ten) 2011 Luzon Northern Sendong (WMO December 13- 1268 (181 2.7 billion Mindanao an name: Washi) 19, 2011 missing) Central Visayas Northeastern Bebeng (WMO May 15-12, 35 (2 missing) 2.25 billion Luzon and Eastern name: Aere) 2011 Visayas
As shown in table 4, several strong storms and typhoons have hit the Visayas and adjacent localities dealing huge destruction to crops and properties. Many lost their homes, have gone missing, or died. Billions were lost due to these cyclones. These storms
would probably have affected less people and damaged fewer properties if the people were more aware of the storms and typhoons that came.
3.1) General Tropical Cyclone Characteristics
Tropical Depression (TD) – a tropical cyclone with 1-minute maximum sustained winds of 53 Kph Tropical Storm (TS) – a tropical cyclone with 1-minute maximum sustained winds of about 63 Kph to 119 Kph Typhoon (Hurricane) (TY) – a tropical cyclone with 1-minute maximum sustained winds of 120 Kph -249 Kph Super Typhoon (STY) – a typhoon with winds of 250 Kph or higher.
Table 5. Frequency, Direction, and Damages of Tropical Cyclones that affected Cebu City from 1965 to 1990. Direction of passage with respect to Typhoon recorded Month Intensity of tropical cyclone occurrence the place damages Tropical Tropical Over/ Typhoon North South Depression Storm Near Asiang /KIT1972) Damage: 145M 3 2 2 2 1 Jan Dead: 204 Missing: 5 Feb Mar 1 1 Diding/WANDA (1971) Damage: P8.3M Apr 1 2 2 1 3 1 Dead: 56 Missing: 39 May 2 1 3 2 4 Jun 1 1 6 8 Jul 1 7 8 Aug 2 1 3 5 1 Sep 2 1 2 1 Ruping/MIKE (1990) Damage: P10,276.5M Oct 1 6 8 2 13 Dead: 508 Missing: 240 Injured: 1,274 Basing/ (1980) Nov 2 1 9 1 11 Damage: P191,000.00 TUndang/AGNES (1984) Damage: P 8M Dec 3 3 4 4 5 1 Dead: 895 Missing: 272 Injured: 2,526 Total 16 18 45 12 62 5
Table 5 shows that 16 or 20% of the tropical cyclones that hit Cebu City are tropical depressions, 18 or 23% are tropical storms, and 45 or 57% are typhoons, five of which were most destructive. Among the directions, 62 or 79% of the storm usually come from the north.
Table 6. Storm Surges that hit Cebu City Typhoon that Date of Waveheight Place(s) affected generated storm occurrence (meters) surge October 12-15, 1912 Consolacion, La Union 9.1 Aug 31-4 Sep 1985 San Fernando, La Union 3.25 Ruping/MIKE Damage: P10,276.553M Nov 10-14, 1990 Catmon. Carmen 2-3 Dead: 508 Injured: 1,274 Missing: 240
Storm surges are waves from the shore that arise from cyclones and storms. This usually has a tall height resulting to floods wherever it hits. Table 6 shows that Cebu has only few points that get struck by storm surges, usually at coastal areas and ship ports.
4) Risk Assessment of levels of Storm unto Visayas The following are the Philippine public storm warning signals and its indicators:
• #1 - A tropical cyclone will affect the locality. Winds of 30-60 kph may be expected in at least 36 hours or intermittent rains may be expected. • #2 - A tropical cyclone will affect the locality. Winds of greater than 60 kph and up to 100 kph may be expected in at least 24 hours. • #3 - A tropical cyclone will affect the locality. Winds of greater than 100 kph up to 185 kph may be expected in at least 18 hours. • #4 - A very intense typhoon will affect the locality. Very strong winds of more than 185 kph may be expected in at least 12 hours.
The Visayas is a place that consists of many islands and people tend to live in the shoreline. Houses tend to be made of bamboo, coconut tree, coconut leaves and some base cement. When a tropical depression (TD) occurs, signal #1 is usually called. This may lead to bending of coconut trees, flying off of roofs made of nipa, and damage to rice and crops. When a tropical storm or typhoon occurs, a signal #2 might be called when coconut trees could be broken, agricultural plants may be drowned, nipa houses may be totally unroofed, and it can bring light to moderate damage. A typhoon will most likely be called into a signal #3 when trees already get uprooted, electric lines are disrupted, and agricultural products are heavily damaged. A signal #4 will be called if a super typhoon wreak extensive damage on plantations, properties, and buildings.
VI. Proposed Actions The proponents of this study propose that barangays install warning signals to alert residents quickly in cases of typhoons. Moreover, the residents should have an emergency plan that includes an evacuation plan, list of emergency supplies, restoration plans, and other important things, so that they will know the things that should be done during typhoons.
VII. Impacts of the Study This study would inform and increase the awareness of the people, not just in the Visayas region but also in the other parts of the country, regarding typhoons, climate types, tropical cyclone characteristics, and the Philippine public storm warning signals. Knowing this information would help the people prepare for typhoons. Moreover, the actions proposed in this study could be used by those in areas that are frequently hit by typhoons.
VIII. References Blanche, R. (2012). List of retired typhoon names: list of retired typhoons. Retrieved September 15, 2012 from http://en.wikipedia.org/wiki/List_of_retired_Philippine_ typhoon_ names
Guard, C. (1999). Typhoon vulnerability for Guam. USA: Guam, Department of Commerce, Guam Economic Review
Lao, G. and Cordeta, J. (n.d.). Climatology and susceptibility of the selected major ports of entry to meteorological disasters in the Philippines. Philippines: PAGASA
n.a. (2012). Tropical storm Sendong devastates the Visayas and Mindanao: my reaction article to the Sendong typhoon. Retrieved September 15, 2012 from http://emievil. hubpages.com/hub/Tropical-Storm-Sendong-Devastates-the-Visayas-and-Mindanao
Philippine Atmospheric, Geophysical and Astronomical Services Administration (n.d.). The Philippine public storm warning signals. Retrieved March 15, 2013 from http://kidlat.pagasa.dost.gov.ph/genmet/psws.html
Philippine Atmospheric, Geophysical and Astronomical Services Administration (2012). Typhoons in Visayas: eastern Visayas, western Visayas, and southern Visayas. Retrieved September 15, 2012 from www.pagasa.dost.gov.ph