Climate scientists have long warned that as Arctic temperatures rise, the resulting permafrost melt would, and will, release large quantities of carbon dioxide and methane that had been previously sequestered in the long-frozen ground. This feedback loop–in which rising temperatures result in the release of gases that themselves cause temperatures to rise further–could happen with great speed, resulting in worldwide temperatures rising measurably in the span of a single century.
A new study indicates that we still may have been underestimating the potential speed and severity of permafrost melt and the resulting temperature rise. "Abrupt thawing" of Arctic thermokarsts could release gargantuan amounts of previously-trapped greenhouse gases within the next few decades.
"The mechanism of abrupt thaw and thermokarst lake formation matters a lot for the permafrost-carbon feedback this century," said first author Katey Walter Anthony at the University of Alaska, Fairbanks, who led the project that was part of NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE), a ten-year program to understand climate change effects on the Arctic. "We don’t have to wait 200 or 300 years to get these large releases of permafrost carbon. Within my lifetime, my children’s lifetime, it should be ramping up. It’s already happening but it’s not happening at a really fast rate right now, but within a few decades, it should peak." [...]
Using a combination of computer models and field measurements, Walter Anthony and an international team of U.S. and German researchers found that abrupt thawing more than doubles previous estimates of permafrost-derived greenhouse warming. They found that the abrupt thaw process increases the release of ancient carbon stored in the soil 125 to 190 percent compared to gradual thawing alone. What's more, they found that in future warming scenarios defined by the Intergovernmental Panel on Climate Change, abrupt thawing was as important under the moderate reduction of emissions scenario as it was under the extreme business-as-usual scenario. This means that even in the scenario where humans reduced their global carbon emissions, large methane releases from abrupt thawing are still likely to occur. [...]
"Within decades you can get very deep thaw-holes, meters to tens of meters of vertical thaw," Walter Anthony said. "So you’re flash thawing the permafrost under these lakes. And we have very easily measured ancient greenhouse gases coming out."
TWEET OF THE DAY
BLAST FROM THE PAST
On this date at Daily Kos in 2006—A Sense of Urgency, Please:
It's difficult to appreciate the magnitude of self-censorship in the American media until you're exposed to how the foreign press reports on a given conflict. Watching the news here in Greece has helped to put things into perspective.
Here, and in nations across the globe, America's dirty little secret is exposed for the entire world to see. It's a difficult transition to make, the one from filtered news dolled up in blazing graphics and theme music to this unadulterated version of reality pouring into television sets around the globe. The anchor will usually preface the segment with a warning ("the images you are about see are disturbing, but we feel we have to show them to you"), and before your heart has a chance to tell your mind to look away, you're looking at Iraq. The camera pans the street. It's strewn with debris, not flowers. The blackened skeleton of some family car is in the foreground. There's a screaming woman on her knees, slapping her hands on the ground (the puddle of blood she's in, the reporter kindly reminds us, is that of her son). And suddenly, you feel that all-too familiar feeling as your eyes begin to sting and tear up for the death of a stranger.
Of course, it's not just the death of this particular Iraqi, this stranger that affects us so. It is the death of thousands who preceded him that weigh like a million anvils on our conscience, and it's the inevitable death of thousands more that make the shame rise so quickly to our cheeks when we're confronted with the consequences of our action (or inaction, as it may be).
Monday through Friday you can catch the Kagro in the Morning Show 9 AM ET by dropping in here, or you can download the Stitcher app (found in the app stores or at Stitcher.com), and find a live stream there, by searching for "Netroots Radio.” |