Four degrees and beyond: the potential for a global ... - Amper

104 F. Fung et al.
(a)
(b)
(c)
0 500 1000 1500 2000 2500
(mm yr –1 )
0 200 400 600 800
(mm yr –1 )
0 1000 2000 3000
Figure 1. (a) Global mean annual precipitation, (b) mean annual surface run-off and (c) river basin
WSI for the baseline period (1961–1990).
Total MAR and total population have been calculated and used to compute the
WSI for 112 large river basins across the globe for the baseline period (figure 1c).
The cells have been aggregated to the river basin level as a cell-by-cell analysis of
the WSI would distort the results and represent a highly water-stressed world as
transfers and reallocation of water by rivers, canals or pipelines from one part of
a river basin to another would be ignored [9]. The WSI can be converted into the
popular Falkenmark stress indicator where populations showing water availability
Phil. Trans. R. Soc. A (2011)
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