Science for Action: Water
WMO and its network of National Hydrological Services seeks to improve integrated water resource management to address the urgent need for improved forecasting, monitoring and management of water supplies and to tackle the problem of too much, too little or too polluted water.
On average, a human being cannot survive more than three days without water. Over two billion people live in countries experiencing high water stress, while around four billion people face severe water scarcity for at least one month every year. By 2050, the world’s demand for fresh water will be 20 to 30% higher than it is today.
Most rivers and freshwater bodies are transboundary, and decisions by one country on water resource management often have implications for other countries, thus making water a potential source of both peace and conflict.
Climate and water data underpin the management of surface-water supplies and disaster risk reduction. These include calculations of the frequency and duration of heavy rainfall, the probable maximum precipitation and flood forecasting.
As a result of rising temperatures, the hydrological cycle has accelerated. It has also become more erratic and unpredictable. A warmer atmosphere holds more moisture which is conducive to heavy rainfall. More rapid evaporation and drying of soils worsen drought conditions.
WMO’s annual State of Global Water Resources reports seek to inform policy-making and encourage monitoring, data-sharing and cross-border collaboration. The last five consecutive years (2019-2023) recorded widespread below-normal conditions for river flows, with reservoir inflows following a similar pattern. This reduces the amount of water available for communities, agriculture and ecosystems.
Glaciers suffered the largest mass loss ever registered in the last five decades of record-keeping. 2023 is the second consecutive year in which all regions in the world with glaciers reported ice loss. The International Year for Glaciers’ Preservation 2025 is therefore meant to be a wake-up call to action.
WMO is committed to eight long-term ambitions related to water:
- No one is surprised by a flood
- Everyone is prepared for drought
- Hydro-climate and meteorological data support the food security agenda
- High-quality data supports science
- Science provides a sound basis for operational hydrology
- We have a thorough knowledge of the water resources of our world
- Sustainable development is supported by information covering the full hydrological cycle
- Water quality is known