In 2023, rivers around the world dried up at the fastest rate in three decades, posing a significant threat to global water supplies, according to the latest data from the World Meteorological Organization (WMO).
The WMO’s State of Global Water Resources report highlights that river levels have been consistently lower than average over the past five years, contributing to low reservoir levels worldwide.
This year, more than 50% of global river catchment areas reported abnormal conditions, with many in deficit.
Severe drought has affected vast regions across North, Central, and South America, where the Amazon and Mississippi rivers have reached record-low water levels.
Similarly, major river basins in Asia and Oceania, including the Ganges, Brahmaputra, and Mekong, experienced significantly low water conditions.
The climate crisis is altering water distribution and contributing to extremes of flooding and drought. Despite 2023 being the hottest year on record with dwindling river flows, the world also witnessed catastrophic floods.
These extreme weather events were influenced by the transition from La Niña to El Niño in mid-2023.
While El Niño is characterized by warmer sea-surface temperatures in the east-central equatorial Pacific, La Niña reflects cooler conditions.
However, experts warn that climate change is intensifying the impacts of these natural weather patterns, making their effects more unpredictable.
Flooding has notably impacted areas such as the east coast of Africa, New Zealand’s North Island, and the Philippines.
Conversely, regions like the UK, Ireland, Finland, and Sweden experienced above-normal river discharge, indicating substantial rainfall.
WMO Secretary-General Celeste Saulo emphasized the urgency of the situation, stating, “Water is the canary in the coal mine of climate change.”
She noted that extreme rainfall, floods, and droughts are increasingly threatening lives, ecosystems, and economies, with melting glaciers further jeopardizing long-term water security for millions.
With rising temperatures accelerating the hydrological cycle, water availability is becoming more erratic.
A warmer atmosphere leads to increased moisture, resulting in heavy rainfall, while rapid evaporation worsens drought conditions.
Currently, 3.6 billion people lack adequate access to water for at least one month each year, a number expected to rise to over 5 billion by 2050.
Glaciers have also been severely impacted, losing over 600 gigatonnes of water, the highest loss recorded in 50 years.
Regions such as western North America and the European Alps have seen alarming rates of melting, with Switzerland’s Alps losing approximately 10% of their remaining volume in just two years.
Saulo concluded by stressing the need for improved monitoring and data-sharing regarding the world’s freshwater resources, stating, that they cannot manage what they do not measure. This report seeks to contribute to urgent assessments and cross-border collaboration.