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Scientist Measures an Overlooked Greenhouse Gas

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Scientist Measures an Overlooked Greenhouse Gas

Scientist Measures an Overlooked Greenhouse Gas

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MICHELE NORRIS, host:

This is ALL THINGS CONSIDERED from NPR News. I'm Michele Norris.

MELISSA BLOCK, host:

And I'm Melissa Block.

All of this year we're exploring the causes and effects of climate change in our series Climate Connections with National Geographic. And today, we're going to the Arctic.

NORRIS: Well, Melissa, you went on a reporting trip to Alaska this summer. And today, you're going to introduce us to a scientist who's been studying an aspect of global warming that's been overlooked.

BLOCK: That's right. She's Katey Walter. She is 31 years old. And she is incredibly vibrant and passionate about the work she does.

(Soundbite of woman screaming)

BLOCK: That's Katey right there. You get a sense of it. And she's especially passionate about methane.

NORRIS: Methane? Why methane?

BLOCK: Well, methane is a greenhouse gas and it's 23 times more powerful than carbon dioxide, which means that it's much more efficient at trapping heat. So it feeds into a loop of global warming. And what Katey Walter is saying is that methane is being released from lakes in the far north - in Alaska, Siberia, other places - at a far greater rate than anybody has estimated. So as bad as the projections for global warming are now, if you factor in increased methane emissions, it could be a whole lot worse.

Now, Katey Walter is one of the first people to calculate just how much methane is bubbling out of lakes. And it seems fitting to me, Michele, that somebody as bubbly as Katey Walter is studying bubbles.

Dr. KATEY WALTER (Biogeochemist; Limnologist; Professor, University of Alaska): So if you look out there in the water, see all those bubbles right now, they're coming to the surface. You can see lots of them.

BLOCK: Well, there's dozens of them. Yeah.

Dr. WALTER: There's dozens of them.

BLOCK: And we're going to start in Fairbanks, Alaska, Fairbanks in the center of the state. Katey Walter teaches at the University of Alaska there. And she takes me down a grassy hill to see a large lake that's recently formed. It's formed because as the temperature rises, the permafrost, the permanently frozen ground, is thawing.

Dr. WALTER: And about 10 years ago, I used to ride my bike past here everyday on my way home, and this was solid ground. It was forest. This is a dramatic difference. As far as you can see out here, it's just water, dead trees and methane bubbles.

BLOCK: Those dead or dying trees - birch, spruce and aspen - are tilting into the lake at crazy angles. And there's a name for this now, they call it a drunken forest. As the permafrost thaws, bacteria feed on the carbon stored underground and burp it out as methane.

Dr. WALTER: The carbon that the bacteria are eating has been locked up in the permafrost, in the freezer, for tens of thousands of years. And today with climate change, as more of this permafrost is thawing, you're defrosting that meal for the bacteria.

BLOCK: Katey, I know methane is, you know, it's your subject and you're really curious about. But had you ever look at bubbles like that and just sort of, like, stop. Stop what you're doing out there.

Dr. WALTER: I should, but I have a lot of fun with them. I get more excited the higher the rates of bubbling I find. I'm always looking for a hotspot that's generating even more methane. So...

BLOCK: And that quest for methane hotspots is taking her on her first visit to the northernmost community in the United States - to Barrow, Alaska, on the Arctic Ocean, 340 miles north of the Arctic Circle.

Unidentified Female: Ladies and gentleman, preparation for landing. Sit back. The tray tables should be up and locked.

BLOCK: You can't get to Barrow by road. Flying in is spectacular.

Dr. WALTER: Oh, isn't that beautiful? Look at that.

BLOCK: Lakes of all shapes and sizes stretch to the horizon, shimmering in the sun. They look like gold coins scattered across the tundra.

Katey Walter can't stop smiling as she looks out the window. She tells me, I'm madly in love with lakes.

(Soundbite of airplane engine)

Dr. WALTER: Ooh, it's cold. Wow. This is not (unintelligible).

BLOCK: She's come to Barrow to meet with fellow scientists at the busy research center here. They're studying all kinds of changes in the Arctic. And she's heard about a lake where there's a geyser of gas shooting up. She can't wait to get out on the lake to see what's going on, and she'll take me along.

Katey Walter is what's known as a limnologist - from limne, the Greek word for lake. Her passion for lakes goes back to when she was a girl.

Dr. WALTER: A lot of my childhood was in Oregon and Nevada. So I grew up hiking in the Sierra Nevada Mountains. And being out there with my grandfather and my father. And they would ask, Katey, how did these great big granite boulders, they looked like it had a knife slice through them. How did these boulders split in half so cleanly? And it was ice that got in there. Water - that made its way in, and when it freezes, it expands, and has the strength to crack open those rocks, which is kind of ironic, because years later, that's the same process that I'm studying in the Arctic - is the power of water in its frozen and unfrozen forms.

BLOCK: So, you remember that from when you were a girl?

Dr. WALTER: I remember that. I remember being inspired by those questions. I loved - I love the serenity of being up high in the mountains away from people and where the lakes were. So lakes and wetlands always seemed like a really peaceful place, maybe because people weren't there.

BLOCK: Katey Walter is athletic with long wildly curly golden brown hair and a strong independent streak.

When she was 16, she went to Russia as an exchange student without knowing a lick of the language, and fell in love with the country. She majored in biogeochemistry at the all-women Mount Holyoke College, and kept looking for excuses to go back to Russia.

She got her Ph.D. measuring methane emissions in North Siberian lakes. And she discovered her thrill putting a match to the pockets of methane trapped in lake ice.

Dr. WALTER: You could have fireballs that shoot into the air as tall as spruce tress, or this spring, such a large flame of methane exploded in my face because I didn't do it in a very smart way that it knocked me over backwards and I saw my hair had singed and broken off and was burning in the snow in front of me, and all my eyebrows were singed. So you do have to be careful. But it's a lot of fun just to think that you're out there in this frozen lake and it's burning, just from that natural source of methane.

(Soundbite of helicopter rotor)

BLOCK: The next day we head out from Barrow in a Bell 206 Long Ranger helicopter. The tundra is a patchwork of green polygons, 300 feet below.

Dr. WALTER: Jason(ph), will you let me know when we see the Lake of Death in advance so I could take some photos from the air?

JASON (Helicopter Pilot): Yup. We're almost there.

BLOCK: We're headed to the lake Katey Walter has heard about, the one where there's hotspot, a geyser of gas bubbling from the bottom.

JASON: This is the Lake of Death off to the right.

Dr. WALTER: I can see bubbly. That's awesome. Okay. I'm going to take a picture. Oh, that is it. Look at that.

BLOCK: Some scientists in Barrow have dubbed it the Lake of Death, but the local Inupiat roll their eyes at that. Its real name is collurac(ph), a small bowl or a place to dip water.

(Soundbite of helicopter landing)

We land on the spongy tundra next to the lake. It's a brilliant sunny day.

(Soundbite of inflating a raft)

Dr. WALTER: All right. Shall we push off?

Unidentified Male#1: Okay.

BLOCK: We pile into an inflatable raft - Katey Walter, two other researchers and I. Katey sits up front paddling hard towards the center of the lake. She's looking for a big stream of bubbles. And it takes a while, but eventually...

(Soundbite of water bubbling)

Dr. WALTER: Ooh-hooh. Ooh, this is awesome. Look at that. It's just fizzing. Wow.

BLOCK: A circular area on the surface of the lake is boiling. It's about five feet across. It looks like a soda can is open underneath the water.

(Soundbite of water bubbling)

BLOCK: Katey leans way out over the boat with a funnel and bottle contraption to get samples of the gas. Her arms are soaked to the elbow in the frigid Arctic water.

Dr. WALTER: Okay, guys, we got a good sample.

BLOCK: She'll take the samples back to her lab to test for methane. And back on shore, she does a quick pyrotechnic test.

(Soundbite of lighting a match)

BLOCK: Katey lights a match, makes a torch out of some cotton. She releases the gas from one of the samples she's collected. And a strong flame shoots up.

Dr. WALTER: Oh, it's methane.

Unidentified Male#2: Yeah.

Dr. WALTER: All right, guys.

BLOCK: Katey Walter's enthusiasm for her work is infectious. She's had an exciting few years with lots of research opportunities. But she knows there are tradeoffs. She thinks a lot about balancing her career and the family she'd like to have.

Dr. WALTER: I spent a lot of time asking the next cohort above me, how they handle this, and you do see a lot more men scientists as people advance in their careers than you do see women. So I think a lot of women do make decisions for families rather than doing science head-on. And I've often heard women say, you could do two of the three well, between being a scientist, being a mother and being wife. But few that have said it's easy to do all three.

BLOCK: For now, Katey Walter will keep going back to Siberia to study lakes for months at a time. It's often solitary work, out alone on a lake in a rowboat.

Dr. WALTER: There's something romantic about being out there. So that when that first snow falls in autumn and the sky is a dark blue and the trees have turned yellow. I think what's really exciting about it all is that the lake is going to get cold and it's going to turn over, and this gas is going to come out of it anyways, whether you're there or not. So to be able to be there and watch it, and understand what's going on is a great opportunity.

BLOCK: That's Katey Walter, a biogeochemist.

NORRIS: And a limnologist. Melissa, what projections are scientists making for how much methane will be released at the Arctic?

BLOCK: Well, there are a lot of unknowns. You will hear scientists talking about a potential methane time bomb. We do know that as temperatures rise, the permafrost is thawing, and we know that thawing is accelerating. And by some conservative calculations, that will release at least 10 times the amount of methane that's in the atmosphere right now.

NORRIS: And as you say, that then feeds into global warming.

BLOCK: Right. Remember methane is this very powerful greenhouse gas so that loop of warming cycles around. More methane is released, that means warmer temperatures, which leads to more thawing of the permafrost and then more methane is released.

By the way, Katey Walter shot a video of that geyser that we went out to investigate. It's on our Web site, npr.org. There's also a photo essay of Katey's research in remote Alaska and Siberia. And we'll hear more from our trip to Barrow tomorrow on the program.

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