Page 169 - Climate Change and Food Systems

chapter 5: climate change impact on key crops in africa: using crop models and general equilibrium models to bound the predictions
figure 1
Regions used in completed monographs, potential monographs and omitted countries of Africa
Source: Authors
(Jones et al., 2009), with climate data taken approximately every ten kilometres.
The second approach used in these studies worked with IMPACT, a global partial equilibrium food and agricultural model. The authors used estimates for three different GDP and population scenarios (optimistic, pessimistic, and baseline) and four different climate models. The IMPACT model incorporates assumptions about exogenous technological change for agricultural production, so the predictions for yields are much more optimistic than with the crop model approach, which does not allow for technological change. The biophysical impacts of climate change on crop yield from the DSSAT model are incorporated into alternative scenarios in the IMPACT model, in order to
assess the effect of climate change when market adjustments are also included.
This paper draws heavily on material presented in the three regional overview chapters of the monographs (Jalloh et al., 2013; Waithaka, et al., 2013; Hachigonta et al., 2013), along with material generated in support of the monographs but which may not have appeared in the final publications. For those wishing to gain a deeper understanding of the methodology used in the studies (and thus of the results presented here), please see the methodology chapter in one of the monographs, such as Nelson et al. (2013).
Although national and subnational results are not entirely ignored in this chapter, its focus is primarily on regional statistics (i.e. for East Africa, West Africa, and Southern Africa).
The chapter is organized as follows: First, key trends are reviewed in order to better understand the forces of change that influence the projections
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