Map 1 depicts the results of the underlying water modeling based
on Rosegrant et al. (2012a). This map provides the basis for our
experiment in which basin level water supply for irrigation is
shocked by the percentage change in the IWSR index from 2000 to
2030 (Table A3). By subtracting the 2030 results from their 2000
counterparts, we see an increase of irrigation stress in parts of Asia –
particularly Pakistan (Indus basin, 43%), China (Haihe basin, 64%)
and India (Luni basin, 61%), as well as in East Africa and parts of
South America. Among the nineteen regions in our global economic
model, eleven will experience reduced availability of irrigation by
2030, with the largest reductions occurring in South Asia excluding
India (33%) and China (22%) as demand for irrigation outpaces
significant investments. Irrigation availability will remain virtually
unchanged in Canada and Japan, and will slightly increase in the US