Arctic Code Red: Could Become an Overwhelming Source of Greenhouse Gas -World’s Climate Experts Warn
Last year, The Daily Galaxy reported on the work of Russian scientist, Sergei Zimov, who has been studying climate change in Russia's Arctic for 30 years now. For years Zimov has been warning the scientific community that as massive amounts of organic matter (mammoth dung, etc) become exposed to the air it will drastically accelerate global warming predictions even beyond some of the most pessimistic forecasts. And for years Zimov has been the lone voice in the wilderness warning the world that the permafrost is in danger, and when it goes…we go with it. Zimov has been called a quack and worse, but now it seems his warnings were worth paying attention to.
David McGuire of the U.S. Geological Survey and the University of Alaska at Fairbanks and his colleagues recently released their research results showing that the Arctic has been a carbon sink since the end of the last Ice Age. The artic holds about 800 million metric tons of the global carbon sink. However, McGuire warns, the rapid rate of climate change in the Arctic especially (twice that of lower latitudes) could very well eliminate the sink and instead, make the Arctic an overwhelming source of the greenhouse gas.
“This study is another example of the important role played by USGS and its partners in providing the scientific research that must be the backbone of any actions related to climate change,” said Secretary of the Interior Ken Salazar.
For thousands of years animal waste, and other organic matter left behind on the Arctic tundra, has been sealed off from the environment by permafrost. Now climate change is starting to melt the permafrost and the very real concern is that it will free mass quantities of prehistoric “ooze” from its state of suspended animation.
The arctic could potentially alter the Earth’s climate by becoming a massive source of global atmospheric carbon dioxide. The arctic now traps or absorbs up to 25 percent of this gas, but climate change could very likely alter that amount.
Carbon enters the oceans and land masses of the Arctic from the atmosphere and mostly accumulates in permafrost (the frozen layer of soil underneath the land’s surface). The carbon becomes trapped in the frozen soil.
But recent warming trends could change this balance. Warmer temperatures can accelerate the rate of surface organic matter decomposition, releasing more carbon dioxide into the atmosphere. Of greater concern, says McGuire, is that the permafrost has begun to thaw, exposing previously frozen soil to decomposition and erosion. These changes could reverse the historical role of the Arctic as a sink for carbon dioxide.
“In the short term, warming temperatures could release more Arctic carbon to the atmosphere,” says McGuire. “And with permafrost thawing, there will be more available carbon to release.”
But the even bigger concern, as Zimov has often stated is Arctic methane.
“We don’t understand methane very well, and its releases to the atmosphere are more episodic than the exchanges of carbon dioxide with the atmosphere,” says McGuire. “It’s important to pay attention to methane dynamics because of methane’s substantial potential to accelerate global warming.”
And to complicate matters even more, it turns out that the Earth, just like it’s inhabitants, “burps” every once in a while, and when it does it’s anything but discreet. The last time the world belched up some methane, the entire climate changed drastically and abruptly.
Here’s the scary news: It could very well happen again without warning. Last year, scientists, funded by the National Science Foundation (NSF), reported that mass quantities of the powerful greenhouse gas, methane, escaped from ice sheets that extended to Earth's low latitudes around 635 million years ago, causing a dramatic climate shift from an ice age to a global warming phase. If it happens again, the results will be deadly.
"Our findings document an abrupt and catastrophic global warming that led from a very cold, seemingly stable climate state to a very warm, also stable, climate state--with no pause in between," said geologist Martin Kennedy of the University of California at Riverside (UCR), who led the NSF funded research team. The methane was released gradually at first, but when the clathrates (methane ice stabilized beneath ice sheets) became unstable the ice turned into gas and escaped to the Earths surface where it had a profound effect on the climate.
"What we now need to know is the sensitivity of the trigger," Kennedy said. "How much forcing does it take to move from one stable state to the other--and are we approaching something like that today with current carbon dioxide warming?"
The change "from 'snowball Earth' into a warmer period shows the compelling need for research on abrupt climate change in Earth's history," said H. Richard Lane, program director in NSF's Division of Earth Sciences. "These changes have much to tell us about the modern human-induced threat of rapid climate change."
Scientists believe that the methane clathrate destabilization acted as a runaway feedback loop that quickly increased global warming, and caused the end of the last “snowball” Earth.
"Once methane was released at low latitudes from destabilization in front of the ice sheets, warming caused other c to destabilize," Kennedy said. "Clathrates are held in a temperature-pressure balance of only a few degrees."
What worries scientists is that not all of Earth's methane was released at the time, and there is still plenty waiting to be exhaled. Massive methane clathrates exist in Arctic permafrost right now, and beneath the oceans at continental margins. The hope is that they will remain dormant, but the fear is that warming will trigger them.
Kennedy says it’s a major concern, because it's possible that very little warming could trigger this trapped methane to destabilize. Uncovering the methane reservoir could potentially warm the Earth tens of degrees, he said, and it would happen quickly.
Clathrates side, we’ve got a lot of mammoth poop to worry about. For thousands of years animal waste, and other organic matter left behind on the Arctic tundra, has been sealed off from the environment by permafrost. Now climate change is starting to melt the permafrost and the very real concern is that it will free mass quantities of prehistoric “ooze” from its state of suspended animation.
Zimov’s theory is steadily gaining credibility in the scientific community. "There's quite a bit of truth in it," Julian Murton, member of the International Permafrost Association, told Reuters. "The methane and carbon dioxide levels will increase as a result of permafrost degradation."
"This will lead to a type of global warming which will be impossible to stop," Zimov has said.According to Zimov, when the organic matter left behind by mammoths and other wildlife is exposed to the air by the thawing permafrost, microbes that have been dormant for thousands of years will spring back into action. They’ll begin once again to emit carbon dioxide and methane gas as a by-product. Zimov says though the microbes are tiny, they will start emitting these gases in enormous quantities simply because there are so many of them.
But not only that, but as the permafrost melts, massive clathrate “bubbles” will likely start to burst and accelerate the release of methane gas to a catastrophic level.
Now with other scientists reaching similar conclusions, Zimov has received validation—not that he’s too happy about it. Zimov hopes he is wrong, just like the rest of us. Nothing could be a less glamorous demise as death by mammoth dung. Let’s just hope that there’s enough time for something more exciting (asteroids, escaped mutant lab virus, robot uprising etc.) to get the chance to do us in first.
Posted by Rebecca Sato
U.S. Geological Survey Research