summer. The effect is more significant in the ‘western’ area with its dry summer, but the downstream decrease in impact is still clearly evident.

It should be noted that the patterns of river flow shown in Figure 5 are not intended to be realistic predictions of what will happen to river flows in the Indian Subcontinent, but to illustrate the general principle that the impact of glacier mass loss will decrease downstream, and will be regionally variable, depending on glacier area, the rate of glacier melt, and the magnitude and seasonal distribution of precipitation in the catchment. Semi-arid regions are likely to be the most ad- versely affected, whereas the effect of glacier retreat in monsoonal Asia will probably be buffered by other components of the hydro- logical system. While the results indicate that the more alarm- ist predictions of the impacts of climate change are highly implausible, they do support the idea that glacier recession is likely to have a major impact in some areas. Detailed scien- tific studies of specific regions are urgently needed. It is how- ever also clear that glacial melt is not the only factor impact- ing intensity and timing of water flow. Timing and intensity

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of the monsoon, other rainfall and especially land use prac- tices such as deforestation, overgrazing, agricultural systems and settlement patterns are, on average, even more important for water flow in the lower and thus more densely populated parts of the catchments.

Effects on humans and livelihoods

Supply of and changes in meltwater and runoff from glaciers in high mountains can affect human populations and livelihoods in a number of ways. The term ‘livelihood’ includes the capa- bilities, assets (material and social resources), and activities for ensuring means of living (Carney 1998). Sustainable liveli- hoods deal with the idea of coping with and recovering from stresses and shocks (resilience). Climate change and more variability in water flow resulting in either too much water or too little water increases the vulnerability of mountain liveli- hoods. Downstream impacts of changes in water flow from high mountain glaciers may affect different aspects of human livelihoods. The agricultural and food production systems will