Most of the methane gas dissolves in the ocean before reaching the surface, Ruppel said. The total amount of gas is also much smaller than sources on land, such as cows or gas drilling. "It's probably on the order of a feedlot of methane," Valentine said. However, some shallow-water seeps could vent methane to the surface, and researchers expect that future surveys will uncover even more shallow seeps. These regions only received a cursory look during the survey.
Even though the methane may not escape to the atmosphere, the gas still adds to the ocean's overall carbon budget - which is still a wildly uncertain number.
"It's not a huge number, but it's an important number for us to know," Ruppel said.
Original article on Live Science.
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