The Atlantic Ocean floor off the U.S. East Coast has over 500 methane vents, a new study has found.
The study, conducted by researchers at the Mississippi State University, shows that large amount of methane leaking from the seafloor might be contributing to global warming.
"It is the first time we have seen this level of seepage outside the Arctic that is not associated with features like oil or gas reservoirs or active tectonic margins," said Prof Adam Skarke from Mississippi State University, lead author of the study, according to BBC News.
The team said that they have found the vents, but haven't analyzed the gas released by these sites. Circumstantial evidence suggests that the gas is methane, BBC News reports.
The leaks were spotted in an area between North Carolina and Massachusetts. The researchers say that as much as 90 tonnes of the planet-warming gas might be released into the atmosphere each year via these vents, according to Scientific American.
The study is published in the journal Nature Geoscience.
A sludge of ice and gas called methane hydrate, beneath the seafloor off the East Coast is the source of methane, the researchers said.
Methane is a potent greenhouse gas and is the second-most prevalent greenhouse gas in the environment, according to the Environmental Protection Agency. Although methane's life is shorter than carbon dioxide, it can trap more heat.
A majority of the seeps are located at about 1,640 feet, NBC News reports. The researchers said that methane sludge at this depth is prone to several disturbances.
"Warming of the ocean waters could cause this ice to melt and release gas," Skarke, told NBC News. "So there may be some connection here to intermediate ocean warming, though we need to carry out further investigations to confirm if that is the case," he added.
Related research has shown that Arctic seafloor is releasing as much as 17 teragrams of methane each year.