Over Half of the World’s Lakes are Drying Out, Study Warns

A recent extensive study has raised concerns about the declining water levels in more than half of the world’s largest lakes and reservoirs. The study highlights that the primary factors behind this worrisome trend are climate change and human consumption.

This information carries significant importance due to the fact that approximately a quarter of the global population, which amounts to around 2 billion people, live in areas surrounding these shrinking bodies of water, according to the study.

Consequently, the study, which was published in the reputable journal Science, emphasizes the existing problem of water insecurity. Across the globe, hundreds of millions of individuals lack reliable access to safe water, further exacerbating the issue.

The study’s accompanying editor’s summary stresses the urgent necessity of integrating the impacts of climate change and sedimentation into sustainable water resources management practices.

This approach is crucial to safeguarding vital ecosystem services associated with these bodies of water, such as storing freshwater, ensuring food supply, providing habitats for waterbirds, facilitating the natural cycling of pollutants and nutrients, and supporting recreational activities.

Water levels of 1,972 lakes around the globe

The group of researchers, consisting of experts from various countries, conducted a comprehensive analysis by examining approximately 250,000 satellite images of lake areas.

These images were captured over a span of nearly three decades, from 1992 to 2020. The primary focus was to assess the size and water levels of 1,972 freshwater bodies around the world.

The results of this extensive study revealed that 53% of lakes worldwide experienced a reduction in water storage during the mentioned timeframe.

The shrinking Aral Sea between Kazakhstan and Uzbekistan. It used to be a large saltwater lake, but drought and water diversion for irrigation have caused it to shrink. It is now split into several smaller lakes and has even dried up completely in some parts… #MissionMinerva pic.twitter.com/PlPHvjKYph

— Samantha Cristoforetti (@AstroSamantha) September 6, 2022

To put this into perspective, the total amount of water lost is equivalent to 17 times the volume of  Lake Meads, which is recognized as the largest reservoir in the United States.

The study revealed that the decline in water volume in natural lakes could be primarily attributed to the effects of climate change, including rising temperatures, which lead to increased evaporation, as well as human water consumption. In contrast, sedimentation emerged as the dominant factor contributing to water storage losses in reservoirs.

Historic low water levels in US lakes

It is noteworthy that according to study lead author Fangfang Yao, a CIRES visiting fellow who is now a climate fellow at the University of Virginia, this research represents the first comprehensive evaluation of global trends and factors influencing the variability of water storage in lakes.

The current situation concerning the drought-stricken Colorado River in the United States has been extremely challenging in recent years.

Both Lake Mead and Lake Powell, the country’s second-largest reservoir, have experienced a significant decline in water levels, reaching historic lows.