Hundreds of plumes of methane gas have been spotted erupting into bubbles along the Atlantic coastline from Massachusetts to North Carolina. The plumes cluster into eight separate regions, reports CBS News on Monday, Aug. 25, quoting the journal Nature Geoscience. The identity of the escaping gas has not yet been officially confirmed, but the scientists involved are certain of their explanation, since no other idea “fits as well as methane,” says Adam Skarke, of Mississippi State University, who served as lead author.
So far, 570 gas seeps have been located. The Okeanos Explorer, a National Oceanographic and Atmospheric Administration ship, has been gathering data for two years, by sonar and video. Most of the seeps are found along the continental slope, where the sea bottom drops into the Atlantic basin. And according to Science Daily News, the reservoir of carbon underwater may be 10 times as high as that in the atmosphere, locked up in undersea ice which is releasing methane in increasing amounts.
These seeps are not rare; in fact, they are found in various parts of the ocean floors around the world, but none were expected in the area off the eastern United States, because the area is too shallow and too “passive”, which means there has been little geologic activity over recent centuries, which would allow the bubbles to escape. But if these plumes have eluded detection before this, then it’s likely thousands more lie unnoticed under the water. The original source is probably undersea microbes.
Methane is a greenhouse gas, and a burnable fuel, but there is little chance this particular source of methane could be tapped for exploitation. This negative forecast has not stopped the United States and Japan from starting pilot projects to tap underwater methane.
But it is more likely this is just one more source of unwanted pollution in the atmosphere. Fortunately, much of it will dissolve in the ocean – which causes problems of their own. But scientists see this easily-studied bubble eruption as a new way to study how the introduction of more greenhouse pollution might affect climate change – and how a warming ocean, due to that climate change, might escalate the situation in the future.