tion: one-third of the population, concentrated in developing countries, will live in basins where this deficit is larger than 50 percent” (p. 5). However, it is important to keep in mind that the models contain many uncertainties and assumptions about factors such as patterns of economic growth or the potential of technology to improve resource management, and these uncertainties and assumptions can have a significant effect on the models’ results.
The agricultural sector is currently responsible for around 70 percent of freshwater consumption. Patterns of land use, population growth, and rapid urbanization, along with economic development that may require more water (for power generation or production processes, for example) and changing dietary patterns with impacts on agricultural production that also increase need for water, can be expected to have significant effects on demand, in some cases creating or exacerbating competition for supplies.2 Contributing to the pressure is the fact that many countries depend on water sources that must be shared. As Wolf (2007) noted, “There are 263 rivers around the world that cross the boundaries of two or more nations” (p. 245). In total, these river basins account for just under half of Earth’s land area, are home to 40 percent of the world’s population, and make up some part of 145 countries (Wolf et al., 1999). A number of these basins—the Indus, Nile, Tigris–Euphrates, Jordan, Brahmaputra, and Amu Darya river systems, for example—are in areas of strategic importance for the United States (Office of the Director of National Intelligence, 2012). “In addition, about 2 billion people worldwide depend on groundwater, which includes approximately 300 transboundary aquifer systems” (United Nations–Water, 2008:1). Even in the absence of climate change there are multiple reasons for the intelligence community to pay attention to water issues.
2 “The drivers of this resource challenge are fundamentally tied to economic growth and development. Agriculture accounts for approximately 3,100 billion m3, or 71 percent of global water withdrawals today, and without efficiency gains will increase to 4,500 billion m3 by 2030 (a slight decline to 65 percent of global water withdrawals). The water challenge is therefore closely tied to food provision and trade. Centers of agricultural demand, also where some of the poorest subsistence farmers live, are primarily in India (projected withdrawals of 1,195 billion m3 in 2030), sub-Saharan Africa (820 billion m3), and China (420 billion m3). Industrial withdrawals account for 16 percent of today’s global demand, growing to a projected 22 percent in 2030. The growth will come primarily from China (where industrial water demand in 2030 is projected at 265 billion m3, driven mainly by power generation), which alone accounts for 40 percent of the additional industrial demand worldwide. Demand for water for domestic use will decrease as a percentage of total, from 14 percent today to 12 percent in 2030, although it will grow in specific basins, especially in emerging markets” (2030 Water Resources Group, 2009:6).