Transcript:

music; ambience: cutting roots

“That is the sound of my bread knife cutting into the tundra. It’s like cutting a big cake”

In the Alaskan tundra, below the layer of vegetation lies permafrost: soil that typically remains frozen year-round. But now there’s evidence that permafrost may be thawing, and this could have a serious impact on global climate. Welcome to Pulse of the Planet’s Science Diaries, a glimpse of the world of science from the inside. Ecologist Ted Schuur is trying to measure precisely how much carbon is being released by the tundra. Carbon that’s been stored in living plants and carbon that’s been stored in permafrost.

“You can hear kind of that sound of the knife hitting the ice. So, that’s about 20 centimeters down below the surface.”

Ted’s already clipped off the above ground portion of the plants, and now he’s taking out the roots. Gasses given off by both parts of the plant will be sent to his lab in Florida for radiocarbon analysis.

“And this is all organic matter. It’s, basically, plants that lived and died here, and this stuff is trapped in the soil because it’s slowly breaking down by the activity of bacteria and fungi. Plants are taking up carbon. If that was in complete balance, then carbon would be coming in, but an equal amount would be coming out. We’re interested in this idea where if climate’s changing, we won’t be in balance anymorethat the soil will release more than the plants take in. The way we can detect itif we just measure carbon, it all looks the same, but if we measure these isotopes, like radio carbon, that’s when carbon coming out looks different than carbon coming in. Then, we can measure the whole ecosystem to kind of get an idea of how much of that old carbon is leaving.”

Melting permafrost could release significant amounts of carbon into the atmosphere, and that could potentially speed up global warming processes.

Pulse of the Planet’s Science Diaries are made possible by the National Science Foundation. I’m Jim Metzner.