Arctic Ocean Methane

  • A recent study shows the arctic seabed is releasing up to ten-million tons of methane annually. (Photo Courtesy of Patrick Kelley, U.S. Coast Guard)

New research indicates the Arctic seabed is releasing methane at a rate higher than all the other oceans of the world combined. This recent discovery raises concerns about the pace of global warming. Lester Graham reports:

Transcript

New research indicates the Arctic seabed is releasing methane at a rate higher than all the other oceans of the world combined. Lester Graham reports, this recent discovery raises concerns about the pace of global warming.

Under a shallow part of the Arctic Ocean, the seafloor was thought to be permanently frozen, capping vast stores of methane underneath. Researchers at the University of Alaska Fairbanks have found that frozen cap is beginning to leak large amounts of methane into the atmosphere. Natalia Shakhova is one of the leaders of a team that’s been studying the permafrost under the Arctic Ocean.

“What we’re having now, it’s up to ten-million ton[s] of methane annually escaping from this seabed. That means that permafrost does not serve as an impermeable cap to prevent these leakages any longer.”

Methane is a greenhouse gas 30 times more potent than carbon dioxide. The greatest concern about methane releases had been the permafrost on land… but this underwater release could mean climate changes could accelerate.

For The Environment Report, I’m Lester Graham.

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Thawing Tundra Speeds Up Warming

  • University of Florida biologist Ted Schuur does field work in the Alaska tundra every summer (Photo courtesy of Ted Schuur)

A report in this week’s journal Nature looks at how thawing ground up North might
impact global warming. Amy Mayer spent some time in Interior Alaska with
scientists at Eight Mile Lake:

Transcript

A report in this week’s journal Nature looks at how thawing ground up North might
impact global warming. Amy Mayer spent some time in Interior Alaska with
scientists at Eight Mile Lake:

Permafrost is ground that’s supposed to be frozen all the time. But for decades it’s been
thawing in places.

When that happens, carbon gets released—potentially contributing to the greenhouse
effect.

Ted Schuur’s a biologist at the University of Florida but he spends his summers doing
experiments near Healy, Alaska.

I tagged along during some field visits.

I met Schuur when we were both living in Fairbanks. He lives far away now, but loves
Alaska. You only work here year after year if you do. Summer field work is brutal – tons
of mosquitoes and you work all the time because the sun doesn’t set.

Pretty soon, we’re there.

“This has to be one of my more photogenic field sites that I ever worked at.”

Tundra surrounds us. We’re just north of the Alaska Range. I can see the snow-capped
peaks. We change into rubber boots, pick up our packs, and, after a few steps, we’re on
the tussocks.

Alaskans often say walking on tussocks is like balancing on basketballs. It’s not easy. If
your feet slip off, they get wet. Schuur’s tall and used to this, so he goes faster than me,
and with less bumbling.

Soon, we’re balancing on lumber instead. Schuur and his group try to protect the areas
where they work with narrow boardwalks.

“When we first came out here, we put these boardwalks that we’re walking on now, big
10 feet pieces of lumber – they’re like 2x6s or 2x8s. But we don’t really want to walk on
the tundra because we come here a lot and you’d end up with a trail in no time and
destroy vegetation.”

Schuur knows trudging across the tundra damages it and he tries to minimize that harm.
But in order to answer his questions about the potential greenhouse effect from thawing
permafrost, he has to dig in.

Schuur saws into the tundra with a bread knife.

“It’s very satisfying. It’s like cutting a big cake – though this is a cake with lots of roots in it.”

He cuts up the plants and packs the roots and the tops into jars.

“We’re going to measure respiration of plants.”

Schuur uses a machine to scrub out the carbon from the air that’s in the jars. The plant
tops and roots will continue to respire carbon dioxide until they die. Later, he’ll use fancy
equipment to “date” the carbon that’s left.

He needs the age of the carbon because when he finds older carbon he knows it’s only
recently escaped the frozen ground. That makes it extra in the system.

At first, Schuur learned, new carbon coincides with more plant growth that uses up the
addition. That means no greenhouse effect.

But, later, the permafrost keeps thawing, more old carbon becomes available, and plant
growth just can’t keep up. That means, carbon dioxide ends up in the atmosphere from
the thawing permafrost – just like it does from burning coal or gasoline.

The thawing may ultimately be a bad thing, but to understand and explain it further,
Schuur wants to document it – or even cause some. Next, he says…

“As strange as it seems, I would love to thaw permafrost on a large scale,
experimentally.”

The dilemma, of course, is that causing a thaw means contributing to – in a small way –
a process that might damage or destroy the ecosystem. But we all emit carbon dioxide,
just by driving.

“Even as I do that and I do an experiment where I melt out a little bit of the permafrost, I
think we’re generating this information that’s helping society answer these huge
questions.”

Schuur says the amount of tundra he’d sacrifice is tiny relative to the whole circumpolar
region, where tons of carbon waits in ground that is frozen now but could eventually
thaw.

For The Environment Report, I’m Amy Mayer.

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