Water for irrigation and food production constitutes one of the greatest pressures on freshwater resources. Agriculture accounts for around 70 percent of global freshwater withdrawals, even up to 90 percent in some fast-growing economies.
The cost of adapting to the impacts of a 2°C rise in global average temperature could range from US$70 to $100 billion per year between 2020 and 2050, according to the World Bank.
Water is a primary medium through which changes in human activity and the climate impact with the earth’s surface, its ecosystems, and its people. It is through water and its quality that people will feel the impact of change most strongly.
Collecting water is expected to become increasingly burdensome with global warming. More regions will experience water shortages, as rainfall becomes erratic, glaciers melt and seas rise. People living within 60 miles of a shoreline — a full third of the world's population — will be hit especially hard, as they are most susceptible to increased salinity of coastal potable water sources. As it takes more time to gather water and fuel, the available time for education or other economic and political activities decreases. Already, the majority of children worldwide who do not attend school are girls.
Climate variability, water resource management and economic development are intricately linked. Vulnerability to natural disasters affecting the water supply hampers economic performance and undermines poverty reduction goals and achievement of the MDGs.
148 countries include territory within one or more transboundary river basins. 39 countries have more than 90% of their territory within one or more transboundary river basins, and 21 lie entirely within one or more of these watersheds.
There are numerous examples where transboundary waters have proved to be a source of cooperation rather than conflict. Nearly 450 agreements on international waters were signed between 1820 and 2007.