NASA is studying “thermokarsts” in Alaska, lakes that look like permafrost where they thaw.
These lakes can release high levels of methane, a dangerous climate change gas.
As temperatures rise and more of these lakes appear, this can create a negative feedback loop.
Lakes emerging in Alaska due to melting permafrost are “belching” methane into the atmosphere, a scientist working with NASA said.
These lakes, called thermokarsts, are so full of the climate-damaging gas that it can be seen bubbling to the surface.
More and more of these lakes are emerging as Alaska’s permafrost thaws with rising temperatures and increasing wildfires, according to a 2021 study.
NASA’s Arctic Boreal Vulnerability Experiment (ABoVE) project is studying their effect on climate change, according to a NASA blog post published Thursday.
Thermokarsts are born after the earth thaws and collapses
Thermokarst lakes appear when permafrost, ground that is meant to remain frozen year-round, begins to melt. When this happens, massive blocks of ice wedged into the ground also melt, causing the ground to collapse several meters.
“Years ago, the ground was about ten feet higher, and it was a spruce forest,” said Katey Walter Anthony, an ecologist at the University of Alaska-Fairbanks, describing a thermokarst called Big Trail lake in Alaska.
Walter Anthony has worked with NASA’s ABoVE project to study Big Trail Lake’s effect on climate change.
As water invades the sinkholes left behind, so do bacteria.
“At Big Trail Lake, it’s like opening the freezer door for the first time and giving all the food in the freezer to microbes to decompose,” Walter Anthony said.
“When they break it down, they belch out methane gas,” she said.
There are millions of lakes in the Arctic, but most are thousands of years old and no longer emit much gas, according to the NASA blog post.
Only the newer lakes, such as Big Trail, which appeared less than 50 years ago, emit high levels of the gas.
And this is far from a small amount. Insider has previously reported that these types of lakes emit so much methane that it’s easy to ignite them after a quick poke into the ice, as can be seen in the video below.
Methane is a destructive greenhouse gas
Although carbon dioxide (CO2) remains the main long-term driver of the climate crisis, methane leaks have become a hot-button issue to help control climate change in the short term.
Methane is a greenhouse gas, meaning it keeps heat radiating from the ground trapped in the atmosphere instead of allowing the Earth to cool.
It is much more potent than CO2, about 30 times more efficient at trapping heat. But it also spreads faster than CO2, which remains in the atmosphere, according to the National Oceanic and Atmospheric Administration (NOAA).
“Reducing methane emissions is an important tool we can use right now to reduce the effects of climate change in the short term and rapidly reduce the rate of warming,” NOAA Director Rick Spinrad said earlier.
Methane “also contributes to ground-level ozone formation, which causes approximately 500,000 premature deaths each year around the world,” Spinrad said.
Human activities such as agriculture, fuel exploitation and landfills are major contributors to methane emissions. For example, gas leaks from methane pipelines are increasingly being targeted because they can be detected from space and are easy to fix.
But natural sources such as wetlands can also be major contributors of methane, per NOAA. Understanding how they might develop is important because rising temperatures could cause a “feedback loop” that “would be largely beyond the ability of humans to control,” NOAA said in April.
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