According to a new report from the World Meteorological Organization (WMO), in 2023, global rivers experienced the driest year in over three decades. This indicates significant changes in water availability at a time of increasing demand.
Currently, 3.6 billion people have insufficient access to water for at least one month per year. This number is projected to rise to over 5 billion by 2050, according to UN Water. The world is also falling behind on Sustainable Development Goal 6, which focuses on water and sanitation.
2023 was the driest year for global rivers in 33 years
In the last five years, there has been a consistent trend of below-normal river flows and reduced reservoir inflows, leading to decreased water availability. The State of Global Water Resources report highlights the strain on global water supplies. In 2023, abnormal river discharge conditions were observed in over 50% of global catchment areas, with severe drought in parts of the Americas and reduced water levels in major river basins. Asia, Oceania, and Africa also experienced abnormal discharge conditions, while parts of Northern Europe saw above-normal discharge.
Glaciers suffer the most extensive mass loss in 50 years
Glaciers experienced their largest mass loss in the past five decades. In 2023, all glacier regions reported ice loss for the second consecutive year. Glaciers lost over 600 gigatonnes of water due to extreme melting in western North America and the European Alps. Over the past two years, Switzerland’s glaciers alone lost about 10% of their remaining volume. Snow cover in the northern hemisphere has been decreasing, with May 2023 recording the eighth-lowest extent of snow cover since 1967. Additionally, summer ice mass loss has indicated that glaciers in Europe, Scandinavia, Caucasus, Western Canada North, South Asia West, and New Zealand have surpassed peak water levels, reducing water storage and availability. However, the Southern Andes, Russian Arctic, and Svalbard are still experiencing increasing melt rates.
Climate change influenced extreme hydrological events
In 2023, the world experienced record-high temperatures, leading to prolonged droughts, widespread dry conditions, and a significant number of floods. These extreme weather events were influenced by natural climate conditions, such as the transition from La Niña to El Niño in mid-2023 and human-induced climate change. Africa suffered the most in terms of human casualties, with Libya being particularly impacted. Two dams collapsed in Libya due to a major flood in September 2023, resulting in over 11,000 deaths and affecting 22% of the population. Additionally, floods affected the Greater Horn of Africa, the Democratic Republic of Congo, Rwanda, Mozambique, and Malawi. Southern USA, Central America, Argentina, Uruguay, Peru, and Brazil experienced widespread drought conditions, resulting in a 3% gross domestic product loss in Argentina and the lowest water levels ever observed in the Amazon and Lake Titicaca.
WMO calls for better monitoring and data sharing
“Water is the canary in the coalmine of climate change. We receive distress signals in the form of increasingly extreme rainfall, floods and droughts, which wreak a heavy toll on lives, ecosystems and economies. Melting ice and glaciers threaten long-term water security for many millions of people. And yet we are not taking the necessary urgent action,” said WMO Secretary-General Celeste Saulo.
“As a result of rising temperatures, the hydrological cycle has accelerated. It has also become more erratic and unpredictable, and we are facing growing problems of either too much or too little water. A warmer atmosphere holds more moisture, which is conducive to heavy rainfall. More rapid evaporation and drying of soils worsen drought conditions,” she added.
“And yet, far too little is known about the true state of the world’s freshwater resources. We cannot manage what we do not measure. This report seeks to contribute to improved monitoring, data-sharing, cross-border collaboration and assessments,” said Celeste Saulo. “This is urgently needed.”
The State of Global Water Resources report series offers a comprehensive overview of water resources worldwide. It aims to inform decision-makers and disaster risk reduction professionals in water-sensitive sectors. The report provides new information on lake and reservoir volumes, soil moisture data, glaciers, and snow water equivalents. It aligns with the global Early Warnings for All initiative to improve water-related hazard monitoring and forecasting.
