Dinos did it. Now we're finding out even the Earth passes gas. The gas is coming from sites all over the Arctic where methane gas is escaping as the ice melts. Aside from the obvious comic factor of our planet farting like a giant cow, there is the serious side that sudden releases trapped ancient methane could have an effect on climate change.
After carbon dioxide, methane is the second most important greenhouse gas affecting the atmosphere and levels are rising. Methane comes from all kinds of sources such as landfills, flatulent cows and now as researchers are discovering, areas that had previously been covered by Arctic ice.
Pinning down the source of the Arctic methane hasn't been easy.
First, researchers from the University of Alaska at Fairbanks had to prove the methane was coming from natural sources previously stored under the ice versus every day man made sources. They did this by looking at the ratio of the different isotopes in the methane molecules that would vary dependent on source.
Next, the research team led by Katey Walter Anthony used aerial and ground measurements at some 150,000 sites in Alaska and Greenland that were near the edges of ice cover to determine what was might have caused the methane build up.
The results were interesting — and showed two potential culprits for the ancient methane now bubbling to the top. Some of the gas was coming from natural gas or coal deposits shifting and now being exposed as the ice retreats.
The other source was decaying matter suddenly being released to the surface as the ice melts. Plant matter in receding Arctic lakes, glaciers and fijords could be finally releasing the by products of decay, which is a "younger" type of methane compared to that released by the deposits deep below the surface.
The research team has written an article in the journal Nature Geoscience in which they say this new release of ancient gasses from the Earth could have an impact on climate change:
"If this relationship holds true for other regions where sedimentary basins are at present capped by permafrost, glaciers and ice sheets, such as northern West Siberia, rich in natural gas and partially underlain by thin permafrost predicted to degrade substantially by 2100, a very strong increase in methane carbon cycling will result, with potential implications for climate warming feedbacks."
While climate change is a subject of wide debate amongst scientists and researchers, the study of the Arctic — and Antarctic — ice melts are of great interest to many countries. Some researchers believe if methane release is of concern, it could be many years before its impact could be seen.
Other scientists warn note that data shows atmospheric methane levels are on the rise once again and sizable releases of methane from receding ice can warm the atmosphere enough that it will actually cause more ice melt.
So while the planet's new habit of passing gas could be climate change's equivalent of the tail wagging the dog, at least we know that the scientific community is aware of where this gas is coming from and that is a step in the right direction.