Department of Science and Technology
Philippine Atmospheric, Geophysical and Astronomical Services Administration
Impacts of Drought in the Philippines
by
Rosalina G. de Guzman2
1Presented
at the International Workshop on Drought and Extreme Temperatures:
Preparedness and Management for Sustainable Agriculture, Forestry
2Philippine
Atmospheric, Geophysical and Astronomical Services Administration, Quezon
City, Philippines
Outline
1.
1. Background
Background Information
Information
2.
2. Impacts
Impacts of
of Drought
Drought
3.
3. Adaptation
Adaptation Strategies
Strategies
4.
4. Drought
Drought and
and Early
Early Warning
Warning System
System
Background information
The Philippines
 a natural disaster-prone country
•
•
•
large number of islands (>7,000);
vast, irregular coastline (17,000 kms);
an average of 19.6 tropical cyclones a year (with 8 to 9
crossing the country triggering floods/landslides);
• abundant rainfall, yet some areas are semi-arid; and
• statistically significant increases in daytime/nighttime
temperatures.
 Major
drought years are associated
with El Nino events
 El
Nino years are associated with less
number of typhoons
Observed Mean Annual Mean Temperature Anomalies in the Philippines
Period: 1951-2006 (departures from the 1961-1990 normal values)
1.5
Anomaly
5 year running mean
Temperature Anomaly (°C)
1
Linear (5 year running mean)
0.5
0
y = 0.0109x - 0.2423
-0.5
-1
-1.5
51
56
61
66
71
76
81
86
91
Year
An increase of 0.6104°C from 1951-2006
96
01
06
•Tropical Cyclones tracks in the WNP
Tracks of tropical cyclones that formed in the Western North Pacific (WNP)
during the period 1948-2006 1728 TC ( 1148 entered the PAR) 66% of TC in in
WNP enter or formed in the PAR
ANNUAL FREQUENCY OF OCCURRENCE OF TROPICAL
CYCLONES WITHIN THE PHILIPPINE AREA OF
RESPONSIBILITY (PAR)
35
32
30
27
25
24
23
21
21
25
22 23 23
21
20
19
20
21
17
19
17
16
17
15
20 19
15
14
15
16
18 17
17
16
12
19.4
18
13
11
10
5
0
70
72
74
76
78
80
82
84
86
88
90
92
94
96
98
00
02
Y E A R
An average of 19.6 or 20.0 tropical cyclones (all categories) entered/developed
in the PAR and 8 or 9 made landfall/crossing the Philippines annually.
Impacts to Agriculture
 Drought
Insufficient Water for Irrigation
Reduced Stream flow
Total Crop Loss
Declining Groundwater
Level
Limiting Water Supply for Farm Household Needs
The Philippine Agriculture
10
Ave. Growth rate = 3.69%
(2001 – 2005)
6.49
5
4.56
3.46
4.81
3.95
2.9
3.88
3.14
2.24
0
1996
1997
1998
-5
-6.6
-10
Ave. Growth rate = 1.95%
(1996 - 1999)
1999
2000
2001
2003
2004
2005
2006
Palay Production ( x 1000 MT)
El Nino impacts on rice production
13000
El Nino
11000
10000
El Nino
El Nino
12000
El Nino
9000
8000
7000
6000
5000
82
84
86
88
90
Year
92
94
96
98
Impacts of drought
• Crop failure
• Reduced irrigated areas
State of calamity in La Union
Philippine Star Jul 31, 2007
Angat water supply down to critical level
Actual monthly inflows compared with the normal values (1968-1998) for Angat
reservoir in Luzon during selected El Niño years (million cubic meters).
1991-1992
Month
1997-1998
Actual
Normal
% of
Normal
Actual
Normal
% of
Normal
October
68.0
304
22
90.2
304
30
November
181.0
291
62
43.4
291
15
December
113.0
211
53
86.9
211
41
January
62.0
101
61
52.0
101
51
February
29.0
57
51
28.0
57
49
March
15.0
51
29
20.9
51
41
Total
468.0
1015
46
321.4
1015
31.6
IMPACTS TO WATER SUPPLY
(water shortage)
• Less water for domestic use
• Loss of target collection / income
• Additional operational cost
- Occurrence of water-borne diseases
• Water quality problems
IMPACTS TO IRRIGATION (water shortage)
• Loss of target collection to NIA
(irrigation Service Fee)
• Reduction of farmers income
• Opportunity loss for NIA
• Increase in the no. of crimes
Impacts on Irrigation
140,000
Production/Harvested Area
120,000
100,000
80,000
1998 (1) - 86.60 %
60,000
1998 (2) - 43.94 %
40,000
20,000
0
1
2
1996
1
2
1997
1
2
1998
1
2
1
1999
Production (M T)
2
2000
1
2
2001
1
2
1
2002
Area Harvested (ha)
Irrigated Palay Production in AMRIS
1 – First Semester Harvest (Nov – Mar cropping season/dry) 2
– Second Semester Harvest (Jun – Oct cropping season/wet)
2
2003
1
2
2004
IMPACTS TO HYDROPOWER (water shortage)
• Opportunity losses
• Increase in the use of other
sources of power such as coal,
thermal, etc.
Impacts on Hydropower
Year
Quarter
1997
2
77.98
57.38
-20.60
26.4
3
85.76
64.84
-20.92
24.4
4
139.61
47.44
-92.17
66.0
1
133.59
34.61
-98.98
74.1
2
77.98
27.50
-50.48
64.7
3
85.76
35.22
-50.54
58.9
1998
10-Yr. Ave
(GWH)
Actual
Generation
(GWH)
Difference
% Reduction
List of Drought Events in the Philippines During the Period 1968 - 1998
Date of Occurrence
Areas Affected
Damages
1. 1968-1969
Moderate to severe drought over most of the
Philippines with Bicol Region as most
severely affected
Total of 5x105 mt
of rice and corn production
2. 1972-1973
Central Luzon, Palawan, Visayas and Mindanao
Total loss of 6.3x105 mt of rice and corn production
3. 1977-1978
The whole of Mindanao except Davao
Total loss of 7.5x105 mt of rice and corn production
4. 1982-1983
Oct. 1982 March 1983
Apr. 1983 Sept. 1983
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
Rice and corn pro- duction loss of 6.4x105 mt; insurance
claims amounted to P38 M; hydropower generation loss
was P316 M
5. 1986-1987
Oct. 1986 March 1987
Severe drought affected Bicol Region, Southern
Negros, Cebu and Western Mindanao
Estimated agricultural damages of P47 M
Severe drought affected mainland of Luzon,
Central Visayas and Western Mindanao
Estimated hydro energy generation loss was P671 M
6. 1989-1990
Oct. 1989 March 1990
Drought affected Cagayan Valley, Panay Island,
Guimaras, Palawan and Southern Mindanao;
affected rice and corn area totalled 283,562
hectares; major multipurpose water
reservoirs reduced inflow
Estimated 5x105 mt of rice and corn production losses;
hydropower gene-ration loss of P348 M; 10% cutback in
water production in Metro Manila
7. 1991-1992
Severe drought affected Mindanao, Central and
Western Visayas and Cagayan Valley;
affected agricultural areas of 461,800
hectares
P4.09 Billion agri-cultural losses; 20% shortfall in Metro
Manila water supply
8. 1997-1998
About 70 % of the Philippines experienced severe
drought; about 292,000 hectares of rice and
corn area completely damaged
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
Apr. 1987 Sept. 1987
What can be done?
Other Institutional
/Interventions
Responses
 NDCC to proactively address the
impending issue on water crisis
 National agencies and LGUs to work
together to monitor ground water levels
 Dry spell/Drought Mitigation Plan (risk &
impact assessment, mitigation & response
strategies)
 Crop insurance
Adaptation Strategies
1. Utilization of drought and
submergence tolerant rice varieties
(2008-dry season)
GMA-RICE
2. Use of improved crop varieties that are resistant to pest and diseases
(2006 – 2007)
Bureau of Agricultural Research (BAR) and PhilRice
Bureau of Agricultural Research and CLSU
P 5.0 M
Source: BSWM
Adaptation Strategies
3. Sustainable System of Irrigated Agriculture (SSIA) P 50.0 M (2008‐2010)
National Irrigation Administration
Department of Environment and Natural Resources
Source: BSWM
Adaptation Strategies
4. LOCALIZED IRRIGATION (DRIP IRRIGATION – water is applied by wetting only a part of the soil in the field through emitter.
 Highly efficient as water is conveyed through a pipe system;
 Water is applied directly to each plant such that only the soil near each plant is wetted;
 Facilitates fertigation and thus, could increase yield by 20% to 70%
DRIP IRRIGATION
 Suitable in steep and undulating slopes, and sandy soils
Source: BSWM
Adaptation Strategies
5. NIA has embarked a program to repair and rehabilitate more than 300,000 ha of unserviceable irrigated farmlands 2006 – 2010
Diversion Dams
Storage Dams
Source: BSWM
Adaptation Strategies
6. Intensify establishment of rainwater harvesting structures (e.g. SWIP)
P 1.5 B (2008 – 2010)
Bureau of Soils and Water management
7. Monitoring, provision of shallow tube wells, and fingerling dispersal to vulnerable areas with high impact to Inland aquaculture P 35.5 M Bureau of Fisheries and Aquatic Resources 7
Source: BSWM
Adaptation Strategies
8. NIA has embarked a program to repair and rehabilitate more than 300,000 ha of unserviceable irrigated farmlands 2006 – 2010
Diversion Dams
Storage Dams
Source: BSWM
Adaptation Strategies
9. Intensify establishment of rainwater harvesting structures (e.g. SWIP)
P 1.5 B (2008 – 2010)
Bureau of Soils and Water management
10. Monitoring, provision of shallow tube wells, and fingerling dispersal to vulnerable areas with high impact to Inland aquaculture P 35.5 M Bureau of Fisheries and Aquatic Resources Impacts of Extreme Dry Condition
A.
Rainfed agricultural areas will be severely affected
B.
Potential reduction in stream flows and water yield of the
different water resources;
•
•
•
•
•
•
Small streams and creeks
Small run-of-the-river irrigation systems
Farm ponds, small water reservoirs, and lakes
Large rivers
Large and major reservoirs
Groundwater source; unconfined and confined shallow
aquifers, deep aquifers
C. Potential increase in crop water requirements due to increase in
crop evapo-transpiration; reduction in irrigated areas
Drought Early Warning and Monitoring System
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 / La Niña Task Force
5. Media
6. General Public and other End-Users
For more Information, VISIT us at
http://www.pagasa.dost.gov.ph
Thank you