TADEAS:
Why we need a new economics of water as a common goodhttps://www.nature.com/articles/d41586-023-00800-zToday, the sector concentrates on flows of ‘blue’ fresh water — liquid that runs off the land and is stored in rivers, lakes, reservoirs and underground aquifers. Utilities capture and extract this water locally for drinking and sanitation, agricultural irrigation and industry. They assume it will be continually replenished, naturally, within historical ranges. In many places, that premise already no longer holds.
Each 1 °C of global warming increases global mean precipitation by 1–3%, and it could rise by up to 12% by the end of the century compared with the period 1995–20141. The impacts will be felt unevenly, with the frequency and severity of both floods and droughts rising. Deforestation, land degradation and infrastructure development are also altering precipitation patterns and affecting where water comes from and ends up2. Excessive extraction for irrigation and industry is aggravating water shortages in river basins, from the Colorado in the United States and the Yangtze in China to the Murray–Darling in Australia.
To meet these growing challenges, water must be recast as a global common good. That means states establishing an obligation under international law to protect the global water cycle for all people and generations, and acknowledging that actions in one place have impacts in another — for instance, that deforestation in Brazil affects rainfall in Peru. It means assessing the role and economic value of not just blue fresh water, but also ‘green’ water that is held in the air, biomass and soils. And it means governments and the private sectors reformulating their roles and responsibilities, to develop objectives, policies and funds that can reshape markets and better manage global water supplies.