Airdate: Nov 17, 2004
Scientist: Laurence (Larry) Smith
Peat Bogs: Time Bomb
Peat bogs in western Siberia are a huge carbon store, but they're in danger of thawing out.
music; ambience: helicopter interior
We're in Siberia, flying over the world's largest network of peatlands. Peat is undecomposed plant matter, and this enormous tract of Siberian peat, about the size of Texas, has played a significant role in regulating the amount of greenhouse gasses in our atmosphere. And that, in turn, has had an impact on global warming. I'm Jim Metzner, and this is the Pulse of the Planet.
Larry Smith is an associate professor in the Department of Geography at UCLA. He tells us that peat, when it's growing, absorbs carbon dioxide from the atmosphere, and historically, Siberian peat has absorbed a lot of CO2.
"There’s a lot more peat stored there than we previously realized. Over millennia this region has withdrawn carbon from the atmosphere and stored it in the ground, where it is now locked up in permafrost, or stored at depth."
Now, when peatlands decompose, they release their carbon in the form of methane and CO2 - increasing the level of these greenhouse gasses. Siberian peatlands, with their vast supply of carbon, could be like a ticking time bomb for our atmosphere.
"The peatlands of western Siberia play a larger role in the global climate system than we previously knew. Both in the past, in the sense that they appear at least partially responsible for a large spike in atmospheric methane seen eleven thousand five hundred years ago, and also today. Because they contain a larger amount of carbon than we previously recognized, they are therefore a larger potential carbon source than we previously knew we had to reckon with. Furthermore, climate models for the area suggest that the temperatures in this region will warm rapidly over the next century."
If Siberian peatlands thaw, how would that affect our atmosphere? We'll find out in future programs.
Pulse of the Planet is presented by the National Science Foundation. I'm Jim Metzner.