A new study has found that climate change is leading to lakes becoming less green, with many at risk of permanently turning greenish brown.
Conducted by the American Geophysical Union, the study presents the first “global inventory of lake colors” and takes into account changes in water color to determine water quality.
While not giving a specific time frame, the researchers say one in 10 lakes could change color in the “future”.
Blue lakes are commonly found in cooler regions of the Earth and are not very common, accounting for only 31% of the world’s lakes. Compared to lakes with bluer or browner water, they are generally deeper and more likely to be covered with ice during the winter.
The study, published Thursday in the journal Geophysical Research Letters, shows that rising temperatures, which lead to the loss of ice, are the main culprit behind the lake’s change in color.
Xiao Yang, co-author of the study, said: “No one has ever studied the color of the lake on a global scale.
“There have been previous studies of maybe 200 lakes globally, but the scale we’re trying here is much, much larger in terms of the number of lakes and also the coverage of the small lakes. While we are not studying every single lake on Earth, we are trying to cover a large and representative sample of the lakes we have. “
Covering the colors of 85,360 lakes and reservoirs worldwide between 2013 and 2020, the study’s researchers used 5.14 million satellite images.
The lake’s color change is generally attributed to algae and other sediments, but new research now shows that varying degrees of warming can also affect the color of the water due to climate change. Queen.
The study says potentially affected lakes are found in northeastern Canada, New Zealand, the Rocky Mountains and northern Europe.
According to Catherine O’Reilly, co-author of the study, the change in color of the lakes has already begun, who points to the Great Lakes of North America having “increased algal blooms” and are also “one of the the lake heats up the fastest.”
Yang also says that a similar trend can be seen in arctic regions that are starting to have lakes with “enhanced blueness”.
Changes in lake color can have devastating effects on people who rely on lakes for drinking, domestic use or fishing.
“There may be periods when the water is unusable and the fish species may be gone, so we won’t get essentially the same ecosystem services from those lakes as they move from blue to green,” says O’Reilly.
It could also mean that the lakes will no longer be used for recreational purposes.
“No one wants to go swimming in a blue lake,” says O’Reilly.
“So aesthetically, some lakes that we might have always considered refuges or spiritual places, those places may be disappearing.”
