Rising seas could invade coastal freshwater supplies. Coastal aquifers may be damaged by saline intrusion as salty groundwater rises. Reduced water supplies would place additional stress on people , agriculture , and the environment. Regional water supplies, particularly in developing countries, will come under many stresses in the 21 st century. Global warming will exacerbate the stresses caused by pollution and by growing populations and economies.
Water availability is an essential component of human welfare and productivity.
Much of the world s agriculture , hydroelectric power production, water needs and water pollution control is dependent upon the hydrological cycle, and the natural recharching of surface and groundwater resources. Changes in the natural water availability as a result of global warming would result in impacts which are generally most detrimental in regions already under existing climatic stresses. Even in more benign climates, the effective management of water resources will receive increasing attention as climate change increases the level of competition between potential users for water.