CURWOOD: It’s Living on Earth. I’m Steve Curwood. Science tells us the more greenhouse gases such as carbon dioxide that are released into the atmosphere, the warmer the planet will become. And since the Industrial Revolution and the widespread use of coal, gas and oil, the average temperature of the planet has risen by a degree, and CO2 has reached levels unmatched for hundreds of thousands of years. Now, data from the Mauna Loa Observatory in Hawaii show a sharp spike in the rate of increase of carbon dioxide over the last two years. Scientists say this jump in the rate of growth of CO2 levels could mean that we face a dramatically shortened timetable for addressing global warming. Joining me now is David Schimel, senior scientist at the National Center for Atmospheric Research in Boulder, Colorado. David, welcome to Living on Earth.
SCHIMEL: Thank you very much.
CURWOOD: We know that carbon dioxide levels have been rising for some years now. What’s different now?
SCHIMEL: Over the past decades, the increase in carbon dioxide has been roughly constant, somewhat paralleling the emissions from fossil fuel and other processes. The last two years have been very high growth rates of carbon dioxide in the atmosphere. Two consecutive years is a little bit unusual. The really unusual thing is that they’re not associated with any obvious climactic event that might trigger, say, widespread drought or unusually extensive wildfires.
CURWOOD: What are the possible explanations for this rather dramatic jump over the last two years in the amount of carbon dioxide coming into the atmosphere?
SCHIMEL: The first explanation is the scary one, which is that the steady warming that’s been occurring in the past few decades is somehow triggering a release of carbon from certain types of ecosystems: forests, or northern peatlands, or other types of ecosystems that store large amounts of carbon. And if that were to be the correct explanation, it would be of concern because that’s a feedback; the warmer it gets, potentially the more CO2 is released, contributing a fraction to the warming and then possibly releasing more carbon."
EDIT
http://www.loe.org/ETS/organizations.php3?action=printContentItem&orgid=33&typeID=18&itemID=228&User_Session=a5ae5794d2c25472f58a728b6c89d8ae(Link down to article)