Updated analysis of the level of climate risk faced by the Ghana cocoa sector.

1. Results of a Random Forest suitability classification study
Climate change impacts on
cocoa in Ghana

2. Cooperation with CRIG-COCOBOD

3. Application of a machine learning tool to cocoa in Ghana
Random Forest classification

4. Random Forests for classification
• A forest is an ensemble of
trees. The trees are all
slightly different from one
another.
• The output is the mean
classification
• Very robust against
overfitting
Is the soil good?
Is the dry
season long?
Is the heat
strong?
One decision tree
Source: Criminisi et al 2013

5. Input locations

6. Input locations

7. Soil data included

8. Results
Random Forest classification

9. Current distribution of suitability classes
for cocoa

10. Current distribution of suitability classes
for cocoa
AEZ Bioclim A Bioclim B Soils
Type 1 Low annual precipitation Strong dry season Below average soils
Type 2 Low temperatures Long dry season Average soils
Type 3 Elevated temperatures Reliable precipitation Average soils
Type 4 High temp Low seasonal variation Above average soils

11. Current distribution of suitability classes
for cocoa
• MSNW
 Moist semi-decidious North
West
• MSSE
 Moist semi-decidious South-
East
• ME
 Moist evergreen

12. Current distribution of suitability classes
for cocoa

13. Current distribution of suitability classes
for cocoa

14. Future distribution of suitability classes for
cocoa

15. Future distribution of suitability classes for
cocoa

16. Transition of suitability classes

17. Climate change impact gradient

18. What does this mean for yields?

19. What does this mean for yields?

20. What does this mean for yields?

21. What does this mean for yields?
Current2050s

22. Current2050s

23. Conclusion
• Cocoa production is shaped by climate and soils
• Cocoa soil characteristics are different from other soils in the
country
• Results show four distinct production zones that align with
ecological zones in Ghana:
 Moist semi-deciduous, subtypes NW, (central),SE
 Moist evergreen
• The moist evergreen climate (type 4) will be the dominant climate in
the future
• The moist semi-deciduous (type 1) region in the North West will
become marginal

24. Conclusion
• Yield and production will be affected by climate
change
• Adaptation has to be a priority for the cocoa
sector

25. Questions
Answers
&