Over half of the world’s lakes are shrinking

A new study says global warming and human consumption are causing the world’s lakes to lose water.

The study found that the world’s lakes were shrinking, with warming temperatures and human activity seen as the main causes | Photo Credit: AP/picture alliance

Over half of the world’s lakes have shrunk, according to a new study published on May 18.

An international research team published their findings in the journal Science and found global warming and human activity to be the chief culprits.

Natural lakes and reservoirs contain around 87 per cent of the Earth’s freshwater—only about 3 per cent of Earth’s water is fresh.

The report highlighted the need for water management solutions.

What were some of the findings?

According to the research, led by hydrologist Fangfang Yao of the University of Colorado, the world’s large lakes and reservoirs had shrunk since the early 1990s.

The team of experts said some of the world’s critical freshwater sources had lost water at a cumulative rate of around 22 gigatonnes per year for nearly three decades.

“More than half of the decline is primarily attributable to human consumption or indirect human signals through climate warming,” said Yao who pointed out that warming contributed “the larger share of that”.

Researchers also found that changes in rainfall and run-off, sedimentation, and rising temperatures had caused global reductions in lake levels.

Almost 30 years of satellite data used

The team measured the change in water levels in nearly 2,000 of the world’s lakes and other water bodies and based the report on satellite data collected between 1992 and 2020.

In the United States, Lake Mead lost two-thirds of its water during the 28-year period.

The study also found that unsustainable human use dried up lakes including the Aral Sea in Central Asia and the Dead Sea in West Asia.

Lakes in Afghanistan, Egypt, and Mongolia were hit by rising temperatures, which led to increased rates of surface evaporation.

Scientists said it is necessary to limit global warming to 1.5° Celsius (2.7° Fahrenheit) to avoid the consequences of climate change. The world is currently warming at a rate of around 1.1°C (1.9°F)