In a recent study published in Nature, it was found that there may be hundreds of billions of tons of methane trapped under Antarctica. As noted in an earlier post, Antarctica used to have a very different climate from today - one in which there was a thriving rainforest. As Antarctica’s climate changed this forest became trapped under miles of Antarctic ice. This study suggests that microbes have spent the last 35 million years busily digesting the ancient organic matter that has sat trapped under Antarctic ice, slowly producing a great collection of methane.
It’s important to note that the team of researchers - lead by Jemmah Wadham, of the university of Bristol, England - have not yet actually detected any significant amounts of methane being discharged from beneath the ice. How do they know these microbes are there? This sub-glacial zone has ancient organic matter; is perpetually heated by geothermal processes; is pitch black, and devoid of oxygen. This is a perfect environment for methane-producing microbes.
The paper uses experimental data from other similar glacial environments, to demonstrate the potential for melting glacial systems to produce methane. By modeling the suspected amounts of organic matter under the Antarctic ice, Wadham’s team suggests that Antarctica may be holding anywhere from 70 to 390 billion tons of methane.
What does this mean for us?
Methane is a greenhouse gas. That is to say, when it reaches the atmosphere, like carbon dioxide, it helps to trap radiation from the sun, thus warming the earth. The greenhouse effect is a normal natural process that is absolutely imperative to maintaining life on earth. However with too high a level of greenhouse gasses, the earth can hold in too much radiation from the sun, which can upset the natural processes that make life possible on earth.
As Antarctic ice melts, it is the worry of climate scientists that this will result in a great release of trapped methane. This may accelerate the rate of global warming. We remain unsure as to whether, and to what extent this may occur.