The article highlights several pieces of research on the potential impact of climate change on the world’s water resources in Nature Climate Change and Nature Geoscience’s article collection ‘Water in a warming world’.

Water is of primary importance for life including our own. However, in addition to drinking water and other domestic requirements, vast amounts of freshwater are needed for agriculture and industry, as well as in power generation, so disruptions to supply can be economically crippling. At an international level, disputes over water resources are likely to intensify with human population growth — and climate change could exacerbate such tensions.

Highlighted research includes:

• Earth-system model simulations by the United States’ National Center for Atmospheric Research were assessed to be consistent with historical records, supporting the validity of these models and their conclusion that widespread droughts will increase in the coming decades over many land areas.
• Bark-beetle infestations in North America’s Rocky Mountains that kill lodgepole pine forests will, in turn, impact ground-water supplies in the region according to research from the Colorado School of Mines.
• A review of research on climate impacts on groundwater at University College London identifies the need for systematic groundwater observations.
• Researchers at The Australian National University found increased water extraction has severely compromised water available for the environment in major rivers across the world and calls for a re-balancing between extraction and environmental flows.
• An interview of Pavel Kabat, Director of the Austria-based International Institute of Applied System Analysis, explains the importance of the system analysis approach for identifying potential synergies among different water users to aid climate adaptation.

The highlighted research identifies risks to water resources under climate change and the need for greater focus on water resources in climate change adaptation planning.

1. Disruptions to existing water resources can have significant environmental, social and economic costs.
2. Population growth can increase disputes relating to water resources and climate change could further exacerbate these tensions.
3. Earth-wide simulation modelling suggests that drought is likely to increase over coming decades.
4. Ecosystems are inter-linked so climate change impacts on forests in the Rocky Mountains from increased prevalence of bark-beetles also impacts critical groundwater supplies.
5. Over-extraction from rivers can increase the impacts of climate change as environmental flows are not available for aquatic systems to manage the impacts of climate change.
6. Systems-level thinking and greater research is required to support water resources climate adaptation.
7. The highlighted research identifies risks to water resources under climate change and the need for greater focus on water resources in climate change adaptation planning.