While the name “fire-ice” may sound like an oxymoron, natural gas is very real. Fire-ice or methane hydrate is a natural gas that is frozen solid deep underneath the ocean floor. There is evidence that is previously thawed during periods of warming and released the potent greenhouse gas called methane, according to a study published December 6 in the journal Nature Geoscience. Increasing ocean temperatures from further human-caused climate change could potentially melt more fire-ice, releasing more polluting methane.
[Related: How AI could help scientists spot ‘ultra-emission’ methane plumes faster—from space.]
Why is methane a problem?
According to the Environmental Protection Agency, methane accounts for roughly 16 percent of global greenhouse gas emissions. It is the second most abundant anthropogenic greenhouse gas after carbon dioxide. It is 25 times more effective than carbon dioxide at keeping heat locked in the atmosphere. However, it has a much shorter half-life than carbon dioxide and generally lingers in the air for less than a decade.
Agriculture is one of the primary methane polluters, but methane can come from anywhere food or plants decompose without oxygen, like marshes, landfills, and fossil fuels. In 2021, methane emissions was added to a list of climate change priorities to tackle in the next decade by the Intergovernmental Panel on Climate Change. The methane from fire-ice is also believed to have played a role in past climate changes and methane was linked to current ocean warming in the southern hemisphere in 2020.
Searching the pockmarks
In the new study, an international team of scientists used advanced 3D seismic imaging techniques to study a portion of fire-ice located off the coast of Mauritania in northwestern Africa. According to the Department of Energy, gas hydrates like these were once believed to be rare, but are now thought to exist in vast volumes and to include 250,000 to 700,000…
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