Vulnerability Mapping for Water Stress in Kerala

Abstract

Researchers on global water scarcity analysis concluded that a large share of the world population—nearly two-thirds—will be affected by water scarcity over the next several decades (Shiklomanov 1991; Raskin et al. 1997; Alcamo et al. 1997; Seckler et al. 2003 ; Vorosmarty et al. 2000; Wallace 2000; Wallace and Gregory 2002). The most obvious conclusion from these analyses is that water will be scarce in areas with low rainfall and relatively high population density. Many countries in the arid areas of the world, particularly Central and West Asia and North Africa, are already close to, or below the 1,000 m/capita/year threshold and therefore, this is the part of the world that is most definitely water scarce. The Intergovernmental Panel on Climate Change (IPCC [2007]) points out that water impacts due to climate change are key for all sectors and regions, resulting in decreasing water availability and increased drought in midand low-latitudes exposing hundreds and millions of people to increased water stress. As the human demand for water stress increases and competition among water-utilizing sectors intensifies, water scarcity becomes apparent in many forms. The Fourth Assessment Report of the IPCC points out that freshwater availability in Asia is projected to decrease due to climate change. By the middle of the 21st century, annual average river runoff and water availability projected to decrease by 10–30 per cent, relative to 1900–70 over some dry regions in the mid-latitudes and dry tropics. Further, water availability is projected to be lower for regions supplied by water from glaciers and snow (IPCC 2007).