This chapter explores the future impacts of climate change on freshwater resources and their management, mainly based on research published after the Working Group II Third Assessment Report (TAR; IPCC, 2001). Socio-economic aspects, adaptation issues, implications for sustainable development, as well as uncertainties and research priorities, are also covered. The focus is on terrestrial water in liquid form, due to its importance for freshwater management. Various aspects of climate change impacts on water resources and related vulnerabilities are presented, as well as the impacts on water-use sectors.
- 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.
- Semi-arid and arid areas are particularly exposed to the impacts of climate change on freshwater.
- 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.
- Climate change affects the function and operation of existing water infrastructure as well as water management practices.
- 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 recognized projected hydrological changes with related uncertainties.
- The negative impacts of climate change on freshwater systems outweigh its benefits.