New study reveals danger from below the waters.
By Raif Karerat
While carbon dioxide remains a major threat to the stability of the Earth’s climate, methane, while less intensive on a grand scale, is actually a more stifling greenhouse gas.
A new study has revealed a new and growing source of methane originating from the deep sea that could compound Earth’s global warming worries.
According to United Press International:
In analyzing instances of bubble plumes, columns of rising methane gas bubbles, researchers found a growing number have been measured at a transition zone. The transition zone, beginning a third of a mile below the surface, is significant to stability of methane hydrates — an area where warming water temperatures could encourage sublimation.Â
Researchers at the University of Washington looked at data on 168 bubble plumes observed in recent years, recorded by the sonar of fishing boats and scientific expeditions and found a higher concentration — 14 — in the transition zone than on the seafloor off the coast of Washington and Oregon.
Most methane plumes don’t make it all the way to the surface. They’re converted to CO2 by methane-consuming microbes. However, more bubble plumes could allow more decomposed methane to reach the surface and enter the atmosphere.
The new analysis was detailed in a paper published this week in the journal Geochemistry, Geophysics, Geosystems.
“The results are consistent with the hypothesis that modern bottom-water warming is causing the limit of methane hydrate stability to move downslope, but it’s not proof that the hydrate is dissociating,” explained co-author Evan Solomon, an associate professor of oceanography at Washington.
Solomon and his colleagues are now analyzing the chemical composition of bubble plumes release by seafloor sediments to better understand the likely source of new methane plumes.