Table 10c calculates the changes in the number of animals of each species for each climate scenario. Across all models, the number of beef cattle is predicted to decrease by an average of five per farm in 2020, 10 in 2060, and 15 in 2100. Chickens also decrease in number. In contrast, numbers of goats and sheep are predicted to increase over time. The number of sheep increases rapidly after 2060 according to CCC and CCSR scenarios.

Combining the results from Tables 10a, 10b and 10c, the expected change in net income is shown in Table 10d for each AOGCM scenario. In all cases, there are losses by the year 2020. The CCC scenario predicts a 13% loss, the PCM scenario a 37% loss, and the CCSR scenario a 15% loss in expected net income per household. African farmers are expected to lose income because they must switch to animals that provide lower returns (thus lowering the net income per animal) and reduce the number of animals for most species. These net results are consistent with a traditional Ricardian analysis of the same data (Seo & Mendelsohn 2006a). The damage increases over time: by 2060 between 15 and 40% of expected income is lost, and between 40 and 70% by 2100.

The 95% confidence interval was calculated for all of these estimates using 200 bootstrap runs. The impact estimates are significant for both uniform temperature change scenarios and uniform precipitation change scenarios. They are also significant for the AOGCM scenarios in 2020, 2060, and 2100.

Table 10d also shows the aggregate impact across Africa. The results suggest that the livestock damage will vary from a loss of $8 to $23 billion in livestock income in 2020, from to $9 to $24 billion in 2060, and from $25 to $40 billion in 2100. The PCM scenario predicts little change from 2020 to 2060, and the CCSR scenario predicts the smallest loss in 2100 among the models due to the large decrease in rainfall predicted in this period. The expected income from livestock will fall because of warming but it will rise in some dry scenarios as farmers shift from crops to livestock.

The remaining analysis looks at the consequences of the AOGCM scenarios for small and large livestock farms. Table 11a examines how species choice changes with each AOGCM for small farms. In 2100, the CCC model predicts that dairy cattle and sheep will be chosen more often as the primary animal and goats and chickens less often. The income per animal will tend to fall over time except for sheep. With the CCC scenario, dairy cattle and sheep will provide a higher income in 2100. With the CCSR scenario in 2100, sheep and dairy cattle also provide higher incomes but the effect is much smaller. The number of animals per farm, shown in Table 11c, will tend to fall with warming, again with a few exceptions. With the CCSR and PCM scenarios, the numbers of beef cattle will increase. The changes in the number of goats and sheep are relatively negligible. Finally, in Table 11d, the expected income for small farms will tend to increase over time with the CCC scenario up to $36 per farm or 34% in 2100. The income fluctuates with the PCM and CCSR scenarios over time, resulting in an 8% increase with the PCM scenario and a 5% decrease with the CCSR scenario in 2100.

Table 12a reveals that large farms in 2100 will shift away from beef cattle, goats and chickens in favor of dairy cattle and sheep with the CCC scenario. However, with the CCSR scenario, large farms will move away from beef cattle in favor of dairy cattle and goats. Finally, there will be little shifting of species in the PCM scenario. Table 12b shows that there is a large absolute 17