Page 85 - Climate Change and Food Systems

chapter 3: economic modelling of climate impacts and adaptation in agriculture: a survey of methods, results and gaps
options such as insurance markets) (Konrad and Thumy).
An effective adaptation strategy is defined not only by what types of interventions to enact but what type of governance to consider. Effective adaptation governance can be guided by the subsidiarity concept which stipulates that decisions about economic activity should be taken by the decision unit at the lowest level of aggregation
at which these decisions do not generate major externalities for other decision units (Konrad
and Thumy). A related economic concept is the “correspondence principle” introduced by Oates (1972), which applies to how economic decision rights, the payment burden, and the cost or return of economic activities should be assigned. Applied to adaptation, the correspondence principle suggests that the set of economic players who bear the cost of some adaptation measure, those who earn the economic benefits of this measure,
and those who decide on this measure should coincide (Konrad and Thumy). The need for such governance arrangements is aptly shown in the case of water resource management, where multiple-decision makers are required, including individual farmers, water users’ associations, local and regional authorities up to national governments. Appropriate governance arrangements in this
case would determine lines of authority, rights and responsibilities, and the extent of coordination across these different levels of decision making (Ostrom, 2007; Meinzen-Dick, 2007).
The above definitional considerations on climate adaptation set the stage for the review of economic models presented in this paper. We begin with the climate models, followed by the impact models, before we embark on the economic modelling analysis. We follow the integrated assessment framework schematically presented in Figure 1.
figure 1
Integration of climate (CMIP3), pathway and economic models
Ricordian Models
Urban income
Story lines
Integrated Assessment Models
SRES
General Circulation Models
Downscaling techniques
Pathway Models (crop yields, human health, sea rise, land loss, etc)
Computable General Equilibrium Models
Food security
Partial Equilibrium Models
Land Farm values income
Food prices
Food Food supply Trade
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