The flag of the World Meteorological Organization (WMO) is pictured at the WMO headquarters in Geneva, Switzerland, Sept. 17, 2025. [Photo/Xinhua]

The global water cycle is becoming increasingly erratic and extreme, swinging between deluge and drought, according to a new report released Thursday by the World Meteorological Organization (WMO).

The State of Global Water Resources 2024 report highlights the cascading impacts of too much or too little water on economies, ecosystems, and societies. It finds that only about one-third of the world's river basins experienced "normal" conditions in 2024, while the rest were either above or below normal, a clear imbalance that has persisted for the sixth consecutive year.

WMO notes that 2024 marked the third straight year of widespread glacier loss across all regions. Many small-glacier areas have already reached, or are close to reaching, "peak water"-the point at which glacier meltwater runoff reaches its maximum annual flow before declining as glaciers shrink.

Regionally, the Amazon Basin and parts of South America, as well as southern Africa, were gripped by severe drought. In contrast, central, western and eastern Africa, parts of Asia, and Central Europe experienced wetter-than-normal conditions.

"Water sustains our societies, powers our economies, and anchors our ecosystems. Yet the world's water resources are under growing pressure, while more extreme water-related hazards are increasingly impacting lives and livelihoods," said WMO Secretary-General Celeste Saulo.

Saulo stressed the need for reliable, science-based information, adding: "We cannot manage what we do not measure. Continued investment and enhanced collaboration in data sharing are vital to close monitoring gaps. Without data, we risk flying blind."

The WMO's annual water report provides an authoritative assessment of global freshwater availability, covering streamflow, reservoirs, lakes, groundwater, soil moisture, snow, and ice. It is based on data from WMO members, global hydrological modeling systems, and satellite observations.

The report warns that water scarcity will worsen, citing UN Water estimates that 3.6 billion people already face inadequate access to water for at least one month per year, a figure projected to rise to over 5 billion by 2050, thereby threatening progress on Sustainable Development Goal 6, which focuses on water and sanitation.