1. Climate change and food production: Pakistan
M. Arif Goheer
Global Change Impact Studies Centre (GCISC)
Islamabad – Pakistan
GECAFS IGP CPW&F and APN Launch Workshops
Kathmandu-Nepal, June 27-30, 2006

2. Climate Change
“the greatest challenge facing the world at the beginning of the century”
World Economic Forum Davos, Switzerland 2000

3. Changing Climatic Trends
Increasing concentration of CO2 in the atmosphere
Pre-industrial revolution (1789) 280 ppm
Present (2004) ppm
Expected level (2050) 550 ppm
Rising surface temperatures
Global Av. Temp. rise (20th century) 0.6 °C
Projections for to 5.8 °C
Changing rainfall patterns
Source: IPCC, 2001

4. Depending on the level of GHG emissions and concentration in the atmosphere, the average global temperature would rise between 1.4 oC – 5.8 oC over the 21st Century

5. Climate and Food Production
Weather and Climate are the key factors in food productivity
Being open to vagaries of nature, food production are highly vulnerable
to climate change phenomena

6. Climate Related Parameters of Agricultural Productivity
CO2
Temperature
Solar Radiation
Precipitation
Others (Wind speed and direction, Soil Moisture, Water vapour, etc.)
Basic understanding of these factors helps manipulate plants to meet human needs of food, fiber and shelter
The parameters also help understand impacts of climate change and devise adaptation/mitigation strategies

7. Climate-Water-Food Linkages
Crop Water Demand
Water Availability
Evapo-transpiration (ET)
Agriculture (Crop Yield)
Photosynthetic
Activity
Canal/ground
water
GDD
and Corresponding GSL

8. Projections of IPCC for South Asia
Increase in surface temperature will contribute to snowmelt resulting in risk of floods
Indus river inflows will decrease by 27% by the year 2050
Land degradation will cause land to shrink from present 0.8 ha per capita to 0.3 by 2010
Areas in mid and high latitudes will experience increase in crop yield whereas in lower latitudes will experience a general decrease, under elevated CO2 conditions
IPCC, 2001

9. Semi-arid areas
Crop models showed that increase in temperature of 0.9 and 1.8°C resulted in reduction in length of wheat growing season by 4 and 8 days respectively
At 0.9°C increase in temperature, wheat grain yield increased by 2.5% whereas at 1.8°C increase, the grain yield decreased by 4%
The increase in temp. would reduce the productivity of rice crop due to heat stress and reduction in growing season length

10. Arid areas
Crop modeling studies showed a non significant trend in wheat yields under increased temperature scenarios (0.9°C and 1.8°C)
Wheat straw yields were reduced by 7% and 12% with temperature increases of 0.9°C by 2020 and 1.8°C by 2050

11. Impacts on Food Production
Due to Increasing Temperatures
Shift in spatial crop boundaries will have enormous economic and social impact.
e.g. Rice transplantation, Cotton picking etc.
Increase/decrease in crop yields
Rise in evapotranspiration rates, calling for greater efficiency of water use
Shift in timing of developmental stages of pests in Crop-weed-pest relationships

12. Due to Change in Precipitation Pattern
More dependency on ground water in the face of low precipitation
danger of depletion of aquifer due to injudicious pumping
increased cost of cultivation
soil salinization due to poor quality ground water

13. Effect of water supplies
Decreased Surface Water Supplies
Reduction in yield and quality of crops due to water stress during critical growth stages
Shift in cropping patterns
Nitrogen volatilization losses from ammonical fertilizers

14. b) Increased Water Supplies
Potential development of Water logging and Salinity/Sodicity
Denitrification losses from ammonical and nitrate based fertilizers
Shift in cropping patterns
Increased incidence of plant diseases

15. Extreme Weather Events
In addition to changing climate, increased variability in weather may occur with consequent frequent extreme events such as heat waves, droughts, wind storms and floods having negative impacts on agriculture

16. Pakistan’s Resource Base
LAND (in million hectare)
Geographical area = 79.6
Area under cultivation = 27.6% (21.87)
Crop area irrigated = 22.6% (17.99)
Rainfed Agriculture area = 4.97% (21.87)
Forest = 4.5% (3.61)
Culturable waste = 11.7% (9.31)
Range Lands = 59% (46.96)

17. Cropping Seasons Rabi Kharif November-April May-October
Wheat, Lentil, Chickpea
Kharif
May-October
Rice, Maize, Mungbean, Cotton

18. Agricultural productivity
Crop
Yield
Wheat
2262 kg/ha
Rice
1836 kg/ha
Maize
1768 kg/ha
Sugarcane
48.1 t/ha
Cotton
579 kg/ha
Fodder
22.3 t/ha
Agricultural Statistics of Pakistan

19. Demand and Production projections with respect to climate change in Pakistan
Commodities
Baseline Requirement
Demands
(000 tonnes)
Production
1995
2020
2050
Wheat
17.9
32.4
43.0
27.46
35.70
Rice
5.1
9.2
12.2
6.21
7.89
S.Cane
41.6
75.3
100.0
50.0
60.0
Cotton
1.8*
3.3*
4.4*
18.00*
25.0*
Fruits
13.8
18.3
Vegetable
4.5
16.2
20.0
Meat
2.1
5.7
7.6
5.0
14.0
Milk
15.3
41.5
55.0
125
* Million Bales
Source: CICERO 2000:2

20. Work Done at GCISC

21. Wheat & Rice Simulation Results
using DSSAT based CERES-Wheat & CERES-Rice models
Semi-arid areas
Arid areas
Humid area
Sub-humid areas

22. Effect of Increase in Temperature and CO2levels on Wheat yields

23. Effect of Increase in Temperature CO2levels and Water Scenarios on Wheat yields

24. Effect of Increase in Temperature CO2levels and Water Scenarios on Wheat yields

25. Growing Season Length (Days)
Effect of Increase in Temperature on Wheat GSL (DSSAT based results to for Cv. Inqalab sown on Nov. 20th)
Temperature
(°C)
Growing Season Length (Days)
Humid
(Shangla)
Sub Humid
(Islamabad)
Semi Arid
(Faisalabad)
Arid
(Multan)
Baseline
246
161
146
137
1 °C
(increase over baseline)
232
155
140
132
2 °C
221
149
135
127
3 °C
211
144
130
123
4 °C
202
138
125
118
5 °C
194
133
121
113

26. Effect of Increase in Temperature and CO2levels on Rice yields in Semi-arid areas of Punjab
Baseline Yield

27. Growing Season Length (Days)
Effect of increase in Temperature on GSL of Rice in Semi arid areas of Punjab (Faisalabad) (Cv. Basmati Super transplanted in 1st Week of July)
Temperature
Growing Season Length (Days)
Baseline
108
(increase over baseline)
1 °C
102
2 °C
100
3 °C 98
4 °C 92
5 °C 89

28. Conclusions Rise in CO2 level only has positive impact on wheat yield
Rise in Temperature shows negative impact on wheat yield
But it could be mitigated if CO2 level = 550 ppm
Negative impact of Rise in Temperature on yield could also be mitigated by increasing number of Irrigations (but…)
Reduction in water resources shows a negative impact on wheat yield
Even 550 ppm CO2 level would not result in sustaining current yield level if water resources reduce
Rise in CO2 levels could sustain the baseline Rice yields up to 1C

29. thanks