Study suggests potential methane reservoirs beneath Antarctica

The ice margin of an Antarctic glacier, depicting frozen lake sediments in the foreground. When ice sheets form, they overrun organic matter such as that found in lakes, tundra and ocean sediments, which is then cycled to methane under the anoxic conditions beneath the ice sheet. (Credit: Image by J. L. Wadham)

The Antarctic Ice Sheet could be an overlooked but important source of methane, a potent greenhouse gas, according to a report in the August 30 issue of Nature by an international team of scientists.
Using an established one-dimensional hydrate model the new study demonstrates that old organic matter in sedimentary basins located beneath the Antarctic Ice Sheet may have been converted to methane by micro-organisms living under oxygen-deprived conditions. The methane could be released to the atmosphere if the ice sheet shrinks and exposes these old sedimentary basins.
If substantial methane hydrate and gas are present beneath the Antarctic Ice Sheet, methane release during episodes of ice-sheet collapse could act as a positive feedback on global climate change during past and future ice-sheet retreat.
"Our study highlights the need for continued scientific exploration of remote sub-ice environments in Antarctica, because they may have far greater impact on Earth's climate system than we have appreciated in the past," said coauthor Slawek Tulaczyk, a professor of Earth and planetary sciences at UC Santa Cruz to the Science Daily. Read full news article here or visit the article in the Nature journal.