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Risks, Impacts, and Adaptation Menus for Study Countries
within the next decade, but by the 2040s water shortages will be severe under all climate scenarios, especially under the high impact scenario. Water shortfalls for the irrigation sector are outlined in table 3.17—the estimates presented are the amounts and percentage shortfalls relative to total water amounts demanded in the basin for irrigation purposes. The most severe irrigation water shortages by the 2040s are forecast to occur in the Syr Darya East basin, an area where irrigation is prevalent and most agricultural production remains highly reliant on irrigation to maintain current yields. Shortages are also forecast for the Syr Darya West and Amu Darya basins, while no shortages are expected for the Aral Sea East and Aral Sea West basins. The same three climate change stressors that affect Moldova and FYR Macedonia also combine to yield an overall negative impact on irrigated crop yields throughout Uzbekistan: • The direct effect of temperature and precipitation changes on crops; • The increased irrigation demand required to maintain even reduced yields; and • The decline in water supply associated with higher evaporation and lower rainfall. All of these effects are worst during the summer growing season. The net effect of these three factors on irrigated agriculture is illustrated in table 3.18, which shows that nearly all crops in all AEZs and basins and across all scenarios are negatively affected by climate change. The direct effects of climate change on livestock also could be severe, but the methods available for quantitatively assessing these impacts are relatively untested. A robust literature establishes that temperature increases decrease livestock productivity, but modeling tools are not available that are suitable for quantifying the effect in the Uzbekistan context. The indirect effect of
Table 3.17 Uzbekistan: Effect of Climate Change on Forecast Annual Irrigation Water Shortfall by Basin and Climate Scenario Climate scenario (shortfall in irrigation water, m3 and percent of total irrigation demand) Low impact 2040s Basin
m3 thousands
Medium impact 2040s
% shortfall
m3 thousands
High impact 2040s
% shortfall
m3 thousands
% shortfall
Syr Darya East
615,927
11.6
940,601
17.5
3,627,991
51.6
Syr Darya West
122,023
1.9
325,942
4.7
2,817,031
34.4
2,174,069
8.7
4,807,848
17.8
8,405,243
28.9
0
0
0
0
0
0
0 2,912,019
0 8.0
0 6,074,391
0 15.4
0 14,850,265
0 33.5
Amu Darya Aral Sea East Aral Sea West Subtotal
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