Lakes shrinking at alarming rate due to climate change, diversion, human impact: study
Rising temperatures due to climate change, combined with the diversion of water for human use, are shrinking our world’s lakes, according to a new study.
The findings, published in Thursday’s edition of “Science,” detail the loss of trillions of gallons of water across the globe that’s been occurring each year since the early 1990s. An analysis of approximately 2,000 of the world’s largest lakes revealed they’re losing roughly 5.7 trillion gallons annually.
From 1992 to 2020, this loss is equal to 17 Lake Meads, North America’s biggest reservoir located in Nevada. It’s also comparable to the total amount of water consumed in the United States in the entire year of 2015.
Although rainfall is increasing in certain areas, lakes are still shrinking, the authors of the study said.
The phenomenon is due to two primary factors: warmer air leading to increased evaporation, and the diversion of water from lakes for agricultural, energy and drinking purposes.
A third, more natural reason for shrinking water resources is linked to changes in precipitation and river runoff. But this could also be the result of climate change, scientists argue.
The dwindling of lakes does not necessarily mean a lack of access to drinking water, they say, but it could lead to an increased demand for lake water, which is used in hydroelectric power and recreational activities like boating.
“More than half of the decline is primarily attributable to human consumption or indirect human signals through climate warming,” said the leader of the study, Fangfang Yao, a climate scientist at the University of Colorado.
The diversion of water for societal use is probably more noticeable because it is “very acute, very local and it has the capability of really changing the landscape,” wrote co-author Ben Livneh, a University of Colorado hydrologist.
Yao, Livneh and their team utilized almost three decades of satellite observation, climate information and computer modeling to study the lakes.
Results showed that over half of the lakes had decreased in size so much that the change could not be attributed to chance, they said.
While scientists have long been aware of the problems of climate change and diversion, this new study offers “a much more complete picture,” said Tamlin Pavelsky, a hydrology professor at the University of North Carolina, who was not part of the study.
Pavelsky added that he’s most concerned for shrinking lakes that are “ecologically important and in populated areas without a lot of other good sources of water,” like Lake Urmia in Iran, the Dead Sea and the Salton Sea in California.
With News Wire Services