IPCC IV AR, WG2 - Chapter 3: Freshwater resources and their management

The chapter on water resources of IPCC Working Group 2's 4th Assessment. The impacts of climate change on freshwater systems and their management are mainly due to the observed and projected increases in temperature, sea level and precipitation variability (very high confidence). Semi-arid and arid areas are particularly exposed to the impacts of climate change on freshwater (high confidence). Higher water temperatures, increased precipitation intensity, and longer periods of low flows exacerbate many forms of water pollution, with impacts on ecosystems, human health, water system reliability and operating costs (high confidence). Climate change affects the function and operation of existing water infrastructure as well as water management practices (very high confidence). Adaptation procedures and risk management practices for the water sector are being developed in some countries and regions (e.g., Caribbean, Canada, Australia, Netherlands, UK, USA, Germany) that have recognised projected hydrological changes with related uncertainties (very high confidence).