Catastrophic tipping point in Greenland reached as crystal blue lakes turn brown, belch out carbon dioxide

[Pelican Press 0]

This is the hidden content, please

• Sign In
• or
• Sign Up

Catastrophic tipping point in Greenland reached as crystal blue lakes turn brown, belch out carbon dioxide

When you buy through links on our articles, Future and its syndication partners may earn a commission.

A Greenland lake near Kangerlussuaq that browned after extreme heat and rain in 2022. | Credit: Vaclava Hazukova

Thousands of Greenland’s crystal-clear blue lakes have turned a murky brown thanks to global warming — and the worst part is that they’ve started emitting carbon dioxide.

Record heat and rain in 2022 pushed the lakes of West Greenland past a tipping point, so rather than absorbing carbon dioxide (CO₂), they began to emit it into the atmosphere, according to a new study.

The changes began in fall, which is normally a snowy time for Greenland. However, heat waves turned snow into rain and thawed the island’s permafrost — frozen ground that stores carbon, iron and other elements. The rains then washed these elements into lakes, turning them brown.

Less sunlight was able to penetrate the lakes as they darkened, which had a ripple effect on the microscopic plankton living in the water. The number of plankton absorbing CO₂ through photosynthesis — the process of turning sunlight into energy — declined, while the amount of plankton breaking down and releasing carbon increased, according to a statement released by the

This is the hidden content, please

• Sign In
• or
• Sign Up

.

The lakes normally absorb CO₂ in the summer, but by the following year they had flipped to become carbon dioxide producers. These types of widespread changes would normally take centuries. Researchers have observed the

This is the hidden content, please

• Sign In
• or
• Sign Up

across the Northern Hemisphere, including the U.S., but it typically takes multiple decades — much longer than the transformation of Greenland’s lakes.

“The magnitude of this and the rate of change were unprecedented,” study lead author

This is the hidden content, please

• Sign In
• or
• Sign Up

, a professor of paleolimnology and lake ecology at the University of Maine, said in the statement.

The researchers published their findings Tuesday (Jan. 21) in the journal

This is the hidden content, please

• Sign In
• or
• Sign Up

.

Related:

This is the hidden content, please

• Sign In
• or
• Sign Up

Roots of historic heat wave

In the fall of 2022, an atmospheric circulation pattern —the large scale movement of air — and a hurricane connected a series of atmospheric rivers from the subtropical and mid-latitude Atlantic to Greenland, according to the

This is the hidden content, please

• Sign In
• or
• Sign Up

, which is part of the European Union’s Earth Observation Programme.

This is the hidden content, please

• Sign In
• or
• Sign Up

are long, narrow regions of the atmosphere that transport heat and water vapor. Climate models predict that atmospheric river activity is likely to generally become

This is the hidden content, please

• Sign In
• or
• Sign Up

around the world with global warming. In 2022, the rivers brought Greenland

This is the hidden content, please

• Sign In
• or
• Sign Up

that was more than 14 degrees Fahrenheit (8 degrees Celsius) warmer than the monthly average in some areas.

Researchers estimated that 7,500 lakes turned brown and began emitting carbon after the fall. But the emissions weren’t the only concern for scientists: these lakes also provide residents of Greenland with drinking water, which could be compromised by the changes.

RELATED STORIES

—Greenland is losing so much ice it’s getting taller

—

This is the hidden content, please

• Sign In
• or
• Sign Up

—’An existential threat affecting billions’: Three-quarters of Earth’s land became permanently drier in last 3 decades

“The influx of dissolved organic carbon and nutrients from the permafrost can also have negative impacts on water supplies, creating bacteria growth that not only affects the water’s taste and smell, but can also potentially cause health problems from increased exposure to metals,” Saros said in a separate

This is the hidden content, please

• Sign In
• or
• Sign Up

released by Heriot-Watt University in the U.K.

Saros added that the dissolved materials could interact with drinking water treatment processes to produce byproducts called

This is the hidden content, please

• Sign In
• or
• Sign Up

, which are a group of chemicals that could have the potential to cause cancers.

The lakes remained brown through the summer of 2024, and the study authors said it was unclear if and when they will revert to blue.

This is the hidden content, please

• Sign In
• or
• Sign Up

#Catastrophic #tipping #point #Greenland #reached #crystal #blue #lakes #turn #brown #belch #carbon #dioxide

This is the hidden content, please

• Sign In
• or
• Sign Up

This is the hidden content, please

• Sign In
• or
• Sign Up