Page 168 - Climate Change and Food Systems

climate change and food systems: global assessments and implications for food security and trade
1. Introduction
As global emissions of anthropogenic greenhouse gases (GHGs) continue relatively unabated, their impact on climate is already being felt. Furthermore, the acceleration of climate change in coming years is virtually assured, due at least in part to the long half-lives of most GHGs. While many of the impacts on people are projected to be modest in the short run (with the exception of increased frequency and intensity of extreme weather events), the adverse consequences
are expected to accelerate as climate change accelerates.
Climate change is likely to affect the agricultural sector more than any other sector, which means that populations that depend most on agriculture could be the ones most adversely affected. This is especially true in most African countries. Many of these countries have limited resources to prepare for and adapt to climate change, or to recover from adverse climate shocks.
In order to help African policy-makers, researchers, non-governmental organizations (NGOs) and donors to better plan and prepare
for climate change impacts, national level studies were recently undertaken2. These studies provide spatially-refined analyses of the impacts of climate on key crops, along with additional analysis that
examines global trends and other factors that are changing with the climate, including gross domestic products (GDP), populations, and agricultural technology development and use. These studies were reported separately for West, East, and Southern Africa. Figure 1 shows the regions covered in this chapter, along with other regions of Africa.
Each study analyzed the range of plausible impacts of climate change by the year 2050, focusing almost entirely on annual crops. Studies used both crop models and global partial equilibrium models, informed by four different climate models and three socio-economic scenarios. In some of the studies on countries in which the livestock sector is important, authors highlighted some key aspects of this sector, using secondary literature.
Two approaches were used to study the impact of climate change on agriculture. The first was to apply the Decision Support System for Agrotechnology Transfer (DSSAT) crop modelling software (Jones et al., 2003) to climate model data, to see how crop yields of major crops would be affected by climate change, not accounting
for market effects, technological changes or adaptation. The second was to use a large global partial equilibrium model focusing on food and agriculture, the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT), to account for population growth and GDP growth in demand, as well as to consider the supply response, as affected by both climate change and technological change.
For the DSSAT crop models, the goal was to compare crops grown in the typical weather of the period 1950 to 2000 with crops grown in weather expected to be typical in 2050. The studies used climate data from four different general circulation models (GCMs – also referred to as “climate models”) so that conclusions would be drawn from a range of scientifically validated possibilities. These models were among those recognized by the Intergovernmental Panel on Climate Change (IPCC) in their Fourth Assessment Report (AR4). These analyses used downscaled climate data
2
These national level studies were published by the International Food Policy Research Institute (IFPRI) in the form of three monographs on agricultural adaptation to climate change in Africa: one for West Africa (Jalloh et al., 2013); one for East Africa (Waithaka et al., 2013); and one for Southern Africa (Hachigonta et al., 2013). These were produced
in partnership with several regional institutes: Conference des Responsables de Recherche Agronomique Africains (CORAF – Conference of the Agricultural Research Leaders in West and Central Africa), Association for Strengthening Agricultural Research in Eastern and Central Africa (ASARECA), and Food, Agriculture and Natural Resources Policy Analysis Network (FANRPAN), and with support from the Consultative Group on International Agricultural Research (CGIAR) research programme on Climate Change, Agriculture and Food Security (CCAFS) and the Federal Ministry for Economic Cooperation and Development, Germany.
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