Page 109 - Climate Change and Food Systems

international agricultural trade as well as alter its geography. Although the overall increase in world food exports is only modest, some types of inter- regional food trade are strengthened, with North America and Europe shown to export more to Asia.
Recently, as part of the Agricultural Model Intercomparison and Improvement Project (AgMIP), an ensemble of ten global economic models (six general equilibrium models and
four partial equilibrium models of the agriculture sector) ran coordinated scenarios to estimate
the likely impacts of climate change and socioeconomic drivers on international trade in agrifood commodities (Nelson et al., 2014; von Lompe et al., 2014). The model results (reported by Ahammad et al., in chapter 10 in this volume) show a general agreement on an increasing role for trade under climate change, but the extent of the changes in trade varies substantially between models.
To sum up the above review on climate and trade, it is our view that work in this area is only
at the beginning. Although a number of models have reported the positive role trade could play as an adaptation mechanism, many important environmental issues related to trade and climate remain unanswered.14 Among the critical climate- trade issues that require further investigation:
(i) More robust evidence of the implications of climate impacts on future food supply in light of projected resource shortages, reduced yields and other climate-induced resource base changes (e.g. sea level rise, loss of crop land, irrigation shortage).
(ii) Better evidence integrating demand-side food drivers (food waste, diets, eco-labelling) and climate-induced supply changes (reduced
14 Kanemoto et al., 2014 show that while developed countries have been able to report decreasing CO2 emissions under the Kyoto protocol, they have
done so largely by displacing emission-intensive production offshore. Using a new highly detailed account of emissions embodied in international trade, the authors find that when trade is accounted for, the authors showed that the CO2 emissions by Kyoto signatory countries have actually gone up.
yields, irrigation water shortages, cropland and quality loss, including from sea level rise) and their implications for trade.
(iii) Evidence on policy-induced growth of “gray” (or dirty) trade versus “green” (emission-saving) trade and the indirect effect of carbon/energy taxes on agricultural and food trade.
(iv) Integrated energy-food systems, including biofuels, and the implications of climate change on food supply and variability, price volatility, land use change and trade patterns.
(v) Better integrated water-food-climate systems and quantified impacts of water scarcity on food supply, prices and trade patterns.
5.2 Farm- and household-level models
Given that much of adaptation in agriculture is local and can be carried out autonomously by individual farmers and household agents, understanding adaptation decision-making at the farm level is
an important requirement for adaptation policy. Household models of farmer decision making
on adaptation can apply either econometric
or simulation techniques. Econometric studies use observed cross-sectional, time series, or panel data to examine the nature of observed adaptations or estimate climate change effects
to which farmers have adapted. Advantages
of an econometric approach include reliance
on real-world data, and an ability to reflect the joint costs and benefits of multiple adaptation strategies to the extent that they are employed together (IPCC, 2014). Nhemachena et al. (2014), use a multivariate probit model to simultaneously examine the determinants of adaptation at
the farm level in a three-country study from southern Africa. Seven dependent variables (different varieties, planting different crops, crop diversification, and different planting dates, diversifying from farming to non-farming activities, increased use of irrigation, and increased use of water oil conservation techniques) were regressed against 17 independent (explanatory) variables.
chapter 3: economic modelling of climate impacts and adaptation in agriculture: a survey of methods, results and gaps
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