1. Adapting agriculture to climate risk: a case study of Ceres - South Africa Abiodun Ogundeji1, Henry Jordaan1 and Jan Groenewald1 Department of agricultural economics University of the Free State, South Africa.
November 21, 2018November 21, 2018

2. Introduction
Climate change and the impact upon already scarce water resources are of global importance
Acute for water scarce countries such as South Africa
Changes in the water supply will inevitably affect the water availability for different users.
Water demand pressure driven by
global temperature surges, population growth, degradation of water quality, lack of efficient water management (accentuate water scarcity).

3. Introduction Economic impact on agriculture
changes in farm profitability, prices, supply, demand, trade, and regional comparative advantage.
Both the demand for and supply of water for irrigation will be affected by changes in the hydrological regimes
concomitant increases in future competition for water with non-agricultural users, owing to population and economic growth.
Climate change is also expected to affect future winter chill
potentially have a major impact on fruit species with chilling requirements

4. Introduction
Insufficient winter chill can severely affect fruit yields and fruit quality, leading to:
delayed foliation
reduced fruit set and fruit quality
inconsistent bud break and leaf development, and non-consistent fruit growth
Significant impact on the productivity of such tree crops and also the economy of the production region and country

5. problem statement
Integrated models applied in CC adaptation
The focus of most previous studies was on the regional impacts of climate change and the adaptation thereof (Callaway et al and Louw et al. 2012).
What about farm level impacts?
Research on crop water use has received much attention in the recent past (Grove, 2007, Annandale et al., 2011, Van Averbeke et al., 2011)
very few have considered future climate.
Attention has been paid to increase in temperature (e.g. Callaway et al., 2009 and Louw et al., 2012)
failed to relate it to chill unit and future chill accumulation.

6. To calculate and incorporate the impacts of future crop water requirement and chill unit,
Two additional modules, namely the crop water module and chill unit accumulation module, were developed.
The modules were linked together using the basic features of the farm model developed by Callaway et al. (2008) and Louw et al. (2012) to form the Ceres Dynamic Integrated Model (CDIM).

7. Aim of the study
The aim of this study is to develop an integrated model that can simulate the impact of CC on farm structure (crop combination, water use and welfare of the farmers)
evaluate the impact of different adaptation strategies to CC on the agricultural sectors

8. Study area

9. The study area/2
Ceres is the administrative centre of the Witzenberg Local Municipality
An important agricultural town surrounded by affluent export-oriented fruit farmers
One of the largest deciduous fruit and vegetable producing districts in South Africa
Ceres produces large quantities of fruit juices (the local juicing plant is the largest in South Africa).

10. Farmers experience of CC
Climate change experienced
Same annual rainfall but less rainy days and rain more intense
Winter is coming later – May is drier, September wetter
More extremes, cold + hot
Evaporation increased – higher irrigation demands
Cold units are marginal – ideal is 1000 to 1200, they are only getting 800

11. Resources are scarce

12. Adaptation What kind of adaptations? Changing cultivars
Storage facilities
Drip irrigation cannot be applied to all circumstances – most important is more efficient irrigation and scheduling
Need for the use of rest break chemicals and more spraying – increase in input costs

13. The model

14. The Model
The objective function of the model is to maximise aggregated net disposable income (NDI) of individual farms in Ceres over the planning horizon.
The model maximises an economic objective function, subject to constraints.

15. Future projected change in climate parameters for H10C station
Summary of climate projections applied in hydrological modelling based on A2 emission scenario.
Period
University of CapeTown (UCT)
Present
( )
IPSL-CM4 (“Low”)
ECHAM5/MPI-OM (“High”)
Intermediate future
( )
Future projected change in climate parameters for H10C station
Change in mean annual rainfall
Change in mean annual temperature
Change in Penman Monteith reference potential evaporation
Low
+10%
+20%
+11%
High
+8%
+12%
+7%

16. Results and discussion
Estimated accumulated Richardson chill unit
Years
Present
(1971 – 1990)
Intermediate Future
( ) 1
1298
869 2
1226
760 3
1110
612 4
1416
908 5
1445
992 6
1278
814 7
1203
1038 8
1136
603 9
1297
778 10
1194
664 11
1422
967 12
1276
815 13
1518
1051 14
1354
823 15
1066
692 16
1270
730 17
1180
689 18
1202
697 19
1441
980 20
1481
1036
Apples
Richardson Chill Unit requirements
Golden delicious
1400
Top red / starking
Royal gala
1200
Pears
Forelle
850
Williams bon chretien
Abate Fetel
Apricots
Soldonne
650
Bebeco
700
Ladisun
500
Suaprieight
450
Plums
Angeleno
400
Southern belle
600
Fortune
African delight
250

17. Impact of CC on crop water requirement
Sprinkler
Drip
Base
Future
+% Change
+% Change
Vegetables
(m3/ha)
Potatoes
4130
4650 13
2740
3080 12
Tomatoes
4220
4860 15
2770
3190
Onion
7780
8680
2390 16
Cabbage
3600
4020
2240
2530
Cauliflower
4300
4720 10
2840
3220
Carrots
3920
4390
2180
2490 14
Peas
4460
5050
2650
3050
Pumpkin
3460
3930
2260
2610
Squash
2980
3830 29
1990
2660 34
Butternut
4310
4570 6
2820
3070 9
Lettuce
3560
4450 25
1830
2510 37
Spinach
4520
5130
2570
2920
Beetroot
2790
1970
Melon
3740
4210
2580
2960

18. Impact of Climate change – Base comparison
Impact of Crops (Ha)
IPSL-CMA
Base (Present)
Base (Future)
Fruits
Apples
9.7
4.9
Apricots
3.0
1.5
Pears
219.5
235.0
Nectarine
22.3
12.6
Peaches
117.0
58.5
Wwine
5.9
2.9
Plums
30.5
15.3
Total
407.9
330.7
Vegetables
Potatoes
0.2
0.3
Tomatoes
0.4
Onions
96.8
142.4
Cabbage
51.1
74.1
Cauliflower
37.8
58.2
Beetroot
47.7
60.1
Other vegetables
2.1
2.8
235.9
338.3
Pastures
8.8
2.4
Cereals
11.7
7.6

19. Scenario Development Scenario Explanation Scenario 1
Farm dam capacity for emerging farmers, with winter water rights
Scenario 2
20% increase in farm dam capacity for emerging farmers, winter water right allocation
Scenario 3
20% increase in farm dam capacity for emerging farmers, winter water right allocation increased by 20 %.
Scenario 4
10% increase in water use efficiency
Scenario 5
10% increase in water tariff

20. Farm dam and winter water right adaptation scenario
Crops(Ha)
IPSL-CMA
Base (Future)
Scenario 1 2 3
Fruits
Apples
4.9
Apricots
1.5
Pears
235.0
245.8
Nectarine
12.6
13.1
14.0
Peach
58.5
Wwine
2.9
Plums
15.3
Total
330.7
342.0
342.9
Vegetables
Potatoes
0.3
Tomatoes
0.4
Onions
142.4
146.9
Cabbage
74.1
72.6
71.9
Cauliflower
58.2
65.5
67.5
Beetroot
60.1
63.3
64.8
Other vegetables
2.8
16.3
5.6
338.3
351.8
354.6
Pastures
2.4
3.0
3.1
Cereals
7.6

21. Farm dam and winter water right adaptation scenario

22. Farm dam and winter water right adaptation scenario

23. Water use efficiency adaptation scenario
Crops
IPSL-CMA
Base (Future)
Scenario 4
Fruits (ha)
Apples
4.9
Apricots
1.5
Pears
235.0
239.6
Nectarine
12.6
12.4
Peaches
58.5
Wwine
2.9
Plums
15.3
Total
330.7
335.1
Vegetables
Potatoes
0.3
Tomatoes
0.4
Onions
142.4
144.3
Cabbage
74.1
72.7
Cauliflower
58.2
60.3
Beetroot
60.1
66.2
Other vegetables
2.8
338.4
347.0
Pastures
2.4
2.6
Cereals
7.6

24. Increase in water tariffs adaptation scenario
Crops
IPSL-CMA
Base (Future)
Scenario 5
Fruits
Apples
4.9
Apricots
1.5
Pears
235.0
234.5
Nectarine
12.6
12.7
Peaches
58.5
Wwine
2.9
Plums
15.3
Total
330.7
330.3
Vegetables
Potatoes
0.3
Tomatoes
0.4
Onions
142.4
Cabbage
74.1
74.5
Cauliflower
58.2
Beetroot
60.1
60.3
Other Vegetables
2.8
338.3
339.2
Pastures
2.4
Cereals
7.6

25. Conclusion
Evaluation and adaptation decisions related to agriculture can be made in an integrated framework.
A change in the profile can be expected as a result of climate change and adaptation thereto.
It is unlikely that high water tariffs will reduce the level of water used for production.
Farm dam capacity and winter water allocations seems to be a good adaptation strategy
caution should be taken when considering such an adaptation option

26. Farm dam is a capital intensive infrastructure
if the farm dams don’t fill up, it may worsen the situation of farmers
Benefit and cost of considering a dam as an adaptation option should be done to justify the usage of public funds
On going research

27. Increasing water use efficiency is a good adaptation option for the farmers
A “no regret” adaptation measure
Water resources management strategy is important in ensuring that agricultural production can withstand the stresses caused by climate change
Farmers must be equipped with a collection of management or adaptation tools to overcome climatic differences.

28. Thank You Dankie Mercie
Abiodun Ogundeji
Department of
Agricultural Economics
T: +27(0)