Indices and Early Warning Systems in the Philippines

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1 Holiday Inn Downtown, Lincoln, Nebraska, USA, 8-11 December 2009 Indices and Early Warning Systems in the Philippines Flaviana D. Hilario, Ph.D. Weather Services Chief Climatology and Agrometeorology Division PAGASA/DOST

2 IMPACTS OF ENSO and NON-ENSO ON PHILIPPINE ANNUAL RAINFALL Legend: Potential Areas Under Severe drought impacts Drought impacts with major losses Moderate drought impacts Near normal to above normal condition Way above normal condition Flood damage Severe flood damage RED colored years are EL NINO years, BLUE colored years are LA NINA years and BLACK colored years are NON_ENSO years

3 List of Drought Events in the Philippines During the Period Drought Events Areas Affected Damages Oct March 1983 Apr Sept Oct March 1987 Apr Sept Oct March 1990 Western and Central Luzon, Southern Tagalog Provinces, Northern Visayas, Bohol and Western Mindanao Moderate to severe drought affected most of Luzon, Negros Occidental and Iloilo Severe drought affected Bicol Region, Southern Negros, Cebu, and Western Mindanao; Severe drought affected mainland of Luzon, Central Visayas and Western Mindanao Drought affected Cagayan Valley, Panay Island, Guimaras, Palawan and Southern Mindanao; Affected rice and corn area totaled 283,562 hectares; major multipurpose water reservoirs reduced inflow 6.4 x 105 mt of rice and corn; insurance claims amounted to P38 M; hydropower generation loss was P 316 M Estimated agricultural damages of P 47 M Estimated hydro-energy generation loss was P 671 M Estimated 5 x 105 mt of rice and corn production losses; hydropower generation loss of P 348 M; 10% cutback in water production in Metro Manila Severe drought affected Manila, Central and Western Visayas and Cagayan Valley; affected agricultural area of 461,800 hectares About 70 % of the Philippines experienced severe drought; about 292,000 hectares of rice and corn area completely damaged P 4.09 Billion agricultural losses; 20 % shortfall in Metro Manila water supply 622,106 mt of rice production loss and 565,240 mt of corn amounting to P 3 B; water shortages; forest fires and human health impacts

4 Percent of Normal (monthly rainfall) Generalized Monsoon Index (GMI) Crop Condition Assessment Yield Moisture Index (YMI) Moisture Availability Index (MAI)

5 helps determines the performance of the rains during the season serves as a good indicator of potential irrigation supplies. The GMI for southwest monsoon (GMI sw ) is defined as: GMI sw = w i P i =w 6 P 6 + w 7 P 7 + w 8 P 8 + w 9 P 9 where: w = weight coefficient of ith monthly rainfall for the season P = rainfall amount in the ith month The GMI for northeast monsoon (GMI ne ) is defined as: GMI ne = w i P i =w 10 P 10 + w 11 P 11 + w 12 P 12 + w 1 P 1 where: w = weight coefficient of ith monthly rainfall for the season P = rainfall amount in the ith month

6 a simple index that can assess agroclimatic crop conditions the data required in the computation of YMI 1) crop calendar information, 2) crop coefficient 3) monthly rainfall data it is defined as: YMI = k i P i where: i = indicates the crop stage (1 = planting/transplanting, 2 = vegetative, 3 = flowering, 4 = maturity) k = is the appropriate crop coefficient for the ith crop stage of growth P = is the rainfall during the ith crop stage

7 Interpretation of YMI Percentile Rank Interpretation Potential for flood damage Near normal to above normal crop condition Moderate drought impact with reduced yield Drought impact with major yield losses 0-10 Severe drought impact with crop failure and potential food shortages

8 Percentile Rank of GM Isw for Iba % rank % Rank ye ar

9 Rainfall in Percentile Rank OND

10 CRITERIA For Rainfall Deficit PERCENTAGE RAINFALL CONDITION < 40% way below normal 41% - 80% below normal 81% - 120% near normal > 120 % above normal MODERATE - 1 to 2 months below normal (41%-80%) rainfall condition DRY SPELL - 3 consecutive months of below normal (41%-80%) rainfall condition CRITICAL 1 to 2 months of < or =40% from the normal DROUGHT 3 consecutive months of < or =40% from the normal OR 5 consecutive months of below normal (41%-80%) rainfall condition

11 Actual Rainfall Analysis in Percent of Normal (Sept. to Nov. 2009) PROVINCE %N Sep %N Oct %N Nov PROVINCE %N Sep %N Oct %N Nov Actual Rainfall Analysis in Percent of Norm al (Septem ber to Novem ber 2009) CORDILLERA ADM INISTRATIVE REGION (CAR) REGION VI (W ESTERN VISAYAS) ABRA AKLAN BENGUET ANTIQUE IF U G A O C A P IZ K A L IN G A G U IM A R A S APAYAO IL O IL O M O U N T A IN P R O V IN C E NEGROS OCCIDENTAL R E G IO N I IL O C O S N O R T E REGION VII (CENTRAL VISAYAS) IL O C O S S U R BOHOL LA UNION C E B U PANGASINAN N E G R O S O R IE N T A L R E G IO N II S IQ U IJ O R BATANES REGION VIII (EASTERN VISAYAS) C A G A Y A N BILIRAN IS A B E L A EASTERN SAM AR NUEVA VIZCAYA LEYTE Q U IR IN O N O R T H E R N S A M A R R E G IO N III (C E N T R A L L U Z O N ) W ESTERN SAM AR) BATAAN SOUTHERN LEYTE BULACAN REGION IX (ZAM BOANGA PENINSULA) NUEVA ECIJA ZAM BOANGA DEL NORTE PAM PANG A ZAM BOANGA DEL SUR TARLAC Z A M B A L E S REGION X (NORTHERN M INDANAO) AURORA BUKIDNON NATIONAL CAPITAL REGION C A M IG U IN M ETRO M ANILA LANAO DEL NORTE REGION IV-A (CALABARZON) M IS A M IS O C C ID E N T A L BATANGAS M IS A M IS O R IE N T A L CAVITE R E G IO N X I (D A V A O R E G IO N ) LAG UNA R IZ A L DAVAO Q U E Z O N DAVAO DEL SUR R E G IO N IV -B (M IM A R O P A ) D A V A O O R IE N T A L M ARINDUQUE R E G IO N X II (S O C C S K S A R G E N ) OCCIDENTAL M INDORO SOUTH COTABATO ORIENTAL M INDORO COTABATO R O M B L O N SARANGANI PALAW AN SULTAN KUDARAT R E G IO N V (B IC O L ) R E G IO N X III- C A R A G A ALBAY AGUSAN DEL NORTE C A M A R IN E S N O R T E AGUSAN DEL SUR CAM ARINES SUR SURIGAO DEL NORTE CATANDUANES SURIGAO DEL SUR M A S B A T E ARM M S O R S O G O N BASILAN M AGUINDANAO LANAO DEL SUR SULU

12 Schematic Diagram of NEEWMS DATA BASES HISTORICAL NORMALS EPISODIC EVENTS INFORMATION FROM OTHER SOURCES ANALYSIS/ASSESSMENT METHODOLOGIES AND PROCEDURES NEAR REAL-TIME METEOROLOGICAL DATA CLIMATE UPDATES AND FORECASTS/DROUGHT ADVISORIES/POTENTIAL IMPACT ASSESSMENT END USERS 1. Inter-Agency Committee on Water Crisis Management 2. National Disaster Coordinating Council 3. Inter-Agency Technical Working Group on Cereals and Feed Grains 4. El Niño National Action Team 5. Media 6. General Public and other End-Users