WMO Warns of Intensifying Global Water Extremes: Deluge, Drought and Glacier Loss

The world’s water cycle is becoming increasingly erratic and extreme, with societies now facing intensified swings between devastating floods and prolonged droughts, according to the World Meteorological Organization’s (WMO) State of Global Water Resources 2024 report. The flagship study highlights the cascading impacts of too much or too little water on economies, ecosystems, and human lives — painting a stark picture of the global hydrological crisis.

A System Under Stress

The report found that only one-third of global river basins experienced “normal” conditions in 2024, with the remaining two-thirds recording either excessive or deficient water levels. This marks the sixth consecutive year of imbalance in global hydrology.

“Water sustains our societies, powers our economies and anchors our ecosystems. And yet the world’s water resources are under growing pressure,” said WMO Secretary-General Celeste Saulo. “Reliable, science-based information is more important than ever before because we cannot manage what we do not measure.”

Climate Drivers and Regional Contrasts

The year 2024 was the hottest on record and began with a strong El Niño event, which reshaped global weather patterns and disrupted hydrological systems:

• Severe droughts hit the Amazon Basin, northern South America, and southern Africa, affecting agriculture, electricity generation, and drinking water supplies.

• Excessive rainfall and floods occurred in West and Central Africa, Central Europe, the Lake Victoria Basin, Kazakhstan, Pakistan, northern India, and northeast China.

• South America experienced simultaneous extremes: catastrophic floods in southern Brazil killed 183 people, while Amazon drought continued, impacting 59% of Brazilian territory.

Rivers, Lakes, and Groundwater

Hydrological anomalies were striking across major basins:

• Below-normal river flows plagued the Amazon, São Francisco, Paraná, Orinoco, Zambezi, Limpopo, Okavango, and Orange rivers.

• Above-normal flows swelled the Danube, Ganges, Godavari, Indus, and Niger basins, triggering widespread floods.

• Nearly all of the 75 monitored lakes recorded above-normal surface temperatures in July, worsening water quality and threatening ecosystems.

• Groundwater resources remained under stress: of 37,406 wells monitored across 47 countries, only 38% had normal levels. Persistent over-extraction in arid and semi-arid regions is compounding water insecurity.

Glaciers: Accelerating Ice Loss

For the third consecutive year, glaciers worldwide lost mass at alarming rates, shedding an estimated 450 gigatonnes of ice in 2024. That is equivalent to a block of ice 7 km tall, 7 km wide, and 7 km deep — or enough to fill 180 million Olympic swimming pools.

This contributed around 1.2 millimetres to global sea-level rise in a single year, posing greater risks to low-lying coastal zones.

• Record losses were reported in Scandinavia, Svalbard, and North Asia.

• Colombian glaciers lost about 5% of their total volume in one year.

• Even the Greenland periphery and Canadian Arctic, traditionally more resilient, recorded continued decline.

Human Impacts of Extreme Events

Erratic water patterns drove humanitarian crises worldwide:

• Africa’s tropical zone suffered unusually heavy rains, causing 2,500 deaths and displacing 4 million people.

• Europe endured its worst flooding since 2013, with one-third of river networks exceeding flood thresholds.

• Asia and the Pacific faced record-breaking rainfall and tropical cyclones, resulting in more than 1,000 deaths.

The report also warns that 3.6 billion people already face water scarcity at least one month per year, a figure projected to rise to 5 billion by 2050 unless urgent action is taken.

Call for Monitoring, Data Sharing, and Finance

A recurring theme in the WMO’s assessment is the urgent need for improved water monitoring systems and international data-sharing. Without robust hydrological data, governments and humanitarian agencies are “flying blind” in managing risks and preparing for disasters.

Celeste Saulo called for:

1. Scaling up systematic observations and research to fill data gaps.

2. Strengthening adaptation and early warning systems to protect vulnerable populations.

3. Increasing climate finance to fund water infrastructure and resilience projects, particularly in developing nations.

A Looming SDG Failure

The findings highlight that the world is falling short of Sustainable Development Goal 6 (SDG 6) — ensuring access to clean water and sanitation for all by 2030. Progress is lagging, with growing inequalities in access to safe water, sanitation, and wastewater treatment.

Looking Ahead

The WMO’s State of Global Water Resources report is part of its broader mission to equip policymakers with authoritative data on climate and water. As extreme hydrological events intensify, the report makes clear that global water governance, investment in monitoring, and stronger climate commitments are critical to prevent escalating disasters.

“The question before us,” Saulo said, “is not whether we act, but whether we act in time, together, and with the courage required.”