A team of scientists from the University of Georgia have started investigating a massive concentration of carbon found in the arctic that could significantly alter the effects of climate change.
Aron Stubbins, one of the researchers from the university's Skidaway Institute of Oceanography, said that they are currently trying to determine how a large deposit of ancient carbon, preserved in Arctic permafrost for thousands of years, is now being converted into carbon dioxide and released into the air.
It is believed that the Arctic consists of a substantial amount of carbon formed from the remains of animals and plants that existed over 20,000 years in the past. These remnants eventually transformed into the frozen soil seen today.
Since this same organic material was kept frozen the entire year, it has yet to go through the process of decomposition by bacteria similar to how other organic substances do in warmer climates. It can be compared to how food is preserved through the use of a home freezer.
Stubbins explained that the same process occurs when it comes to permafrost. As soon as the carbon material begins to defrost, bacteria will eventually start the decomposition as well. This will then release the carbon dioxide locked away.
The amount of carbon found in the Arctic soil is more than 10 times as much as the amount released in the atmosphere from burning fossil fuels beginning with the Industrial Revolution, according to estimates by scientists. The ongoing warming of the planet could potentially thaw the frozen carbon and release it into the environment.
"The study we did was to look at what happens to that organic carbon when it is released," Stubbins said. "Does it get converted to carbon dioxide or is it still going to be preserved in some other form?"
Stubbins' team conducted their study at Siberia's Duvanni Yar. They surveyed the streams in the area around the Kolyma River where they discovered streams made entirely of thawed permafrost.
They then measured the age of the carbon, the different forms of carbon in the water, and the level of carbon concentration. They also extracted two samples of microbes found in the area.
Within a span of two weeks, the researchers recorded the changes in the carbon concentration, the composition, and how much carbon dioxide was produced.
They found that the carbon in the permafrost can be used by microbes after 60 percent of the organic material decomposed and was converted into carbon dioxide after two weeks.
Robert Spencer, the study's lead author from Florida State University, said that what made the material attractive to the microbes is its distinct composition of thawed permafrost carbon.
The results of the study also confirmed that the Arctic carbon being used by the bacteria is 20,000 years old, proving that it has yet to be part of the world's carbon cycle at the moment.
"If you cut down a tree and burn it, you are simply returning the carbon in that tree to the atmosphere where the tree originally got it," Stubbins said. "However, this is carbon that has been locked away in a deep-freeze storage for a long time."
"This is carbon that has been out of the active, natural system for tens of thousands of years. To reintroduce it into the contemporary system will have an effect."
The impending release of the Arctic carbon could initiate a process called positive feedback loop. Experts explain that a positive feedback loop happens when massive amounts of carbon in the atmosphere intensify climate warming, causing more permafrost to thaw and more carbon to be released.
According to Spencer, permafrost and the possibility of a positive feedback loop scenario are not part of future climate projections by the Intergovernmental Panel on Climate Change.
Ted Schuur, a biologist from Northern Arizona University, however, offered a different point of view regarding the possible release of carbon once the permafrost thaws.
"The permafrost carbon is not going to explode into the atmosphere catastrophically within just a few years. It's more like it will seep out slowly in small amounts in a very large number of places," Schuur said.
While further analysis is needed to monitor the amount of gasses, such as carbon dioxide, released from the Arctic permafrost, it is believed that these emissions could eventually add up in the environment and cause a major change in the climate.
