While there are still some people arguing that carbon dioxide is not a greenhouse gas that causes warming, for all those not in denial this has been known for at least several decades.
Methane is a far more powerful warming gas, roughly 30 times the warming potential of carbon dioxide. Methane is a gas that is caused by a number of different factors. It is potentially one of the biggest impacts that cattle have on the environment as they release a great deal of methane during their digestive processes.
However a bigger cause of methane buildup is its release from things that are breaking down, be they animal bodies or simply dead plant material.
This is where the problem lies. Antarctica at one point lay far further North and it is thought it was once covered in rainforest. The methane from all this biodegraded material lying under the ice sheet in Antarctica is currently trapped. It is thought that a similar process occurred under the ice sheet of Greenland.
However this is the problem: if humans cause this ice to melt by releasing enough carbon dioxide into the atmosphere, the plug blocking the methane being released will disappear.
The scary news is that such a leak has recently been discovered, in the Ross sea close to the Antarctic continental shelf. Perhaps the only silver lining about this, is that so far the Ross sea doesn’t appear to have been impacted by human triggered warming, so it does suggest that we are not at the start of an uncontrollable release as much as a quarter of the methane on Earth from under the Antarctic ice sheet. It is thought that this leak has been releasing methane for at least eight years.
On the other hand the fact that this methane has been being released without any discernible cause that humans have made, might suggest that occasional large releases of methane are a natural process and therefore we may not be able to stop it happening to our detriment.