Scientists agree that global warming will generally result in milder winters and hotter summers, although there will be differences between countries. In winter it may rain more, but in the summer, it may become dryer. Water resources would generally benefit from wetter winters but warmer summers with longer growing seasons and increased water evaporation would put greater pressure on them.
Changing Evaporation and Rainfall
Water is essential for human life and development. Much of the world's agricultural, hydroelectric power and water supplies depend upon the water cycle. Global warming will affect the water cycle, placing stress on water resources. In some areas of the world water evaporation may increase by a greater amount than rainfall. This would lead to lower water levels in rivers and lakes. Global warming may mean that rainfall becomes concentrated into large storms that could cause problems with flooding.
Hydroelectric Power
Water is used for a number of different purposes that will be affected by global warming. Rivers may become prone to flooding or drought. Hydroelectric power generation depends upon a high water flow to make electricity. If flows decrease, less hydroelectric power will be generated. The supply and demand for water to homes and workplaces may also be affected if the levels of reservoirs and aquifers decrease. Looking after future water resources with care will become increasingly important as global warming takes place.