FIGURE 4 Scenarios of climate change and food security
Food security could improve with high income growth and low population growth . . .
1,800 2,000 2,200 2,400 2,600 2,800 3,000 3,200 3,400 3,600
Developed countries
. . . or decline with low income growth and high population growth
All developing countries
Low-income developing countries
Perfect mitigation CSIRO B1
CSIRO A1B Climate mean
MIROC B1 MIROC A1B
Source: Figure 3.1 in G. C. Nelson, M. W. Rosegrant, A. Palazzo, I. Gray, C. Ingersoll, R. Robertson, S. Tokgoz, et al., Food Security, Farming, and Climate Change to 2050: Scenarios, Results, Policy Options, IFPRI Research Monograph (Washington, DC: International Food Policy Research Institute, 2010). Notes: The dashed red lines show calorie availability in an unrealistic scenario with perfect mitigation (that is, all emissions stop today and the existing momentum in the climate system is also stopped). The solid lines of various colors reflect outcomes with plausible climate results from two general circulation models, each with two scenarios, from the Intergovernmental Panel on Climate Change’s Special Report on Emissions Scenarios. The shift in values in 2025 reflects the assumption that maize-based ethanol will be replaced with cellulosic ethanol around 2025. This change will reduce the demand for maize, lower its price, and make more calories available for human consumption.
context within which they will take place, are still uncertain. Consequently, to design policies that can protect populations vulnerable to climate change and increase the likelihood of achieving sustainable food security, it is critical to under- stand the impacts of climate change under different scenarios. Figure 4 shows how climate change will likely challenge food security. It reports average calorie availability per person per day—an imper- fect measure of food availability—under a range
46 MODEST ADVANCES, STARK NEW EVIDENCE
of climate change scenarios and two overarching scenarios of the development context. Te opti- mistic scenario reflects high income growth and low population growth, representing a situation of sustainable development. Te pessimistic scenario consists of low income growth and high popula- tion growth. Tree messages stand out from the results in
Figure 4. First, sustainable development, embodied in the optimistic scenario, is key to improving the
2010 2015 2020 2025 2030 2035 2040 2045 2050
2010 2015 2020 2025 2030 2035 2040 2045 2050
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126