In the Arctic, carbon dioxide goes down where methane comes upEnlarge / One example of a methane seep (off the coast of Virginia, in this case). (credit: NOAA Okeanos Explorer Program)
Reports of methane bubbling up from the bottom of the East Siberian Sea may have induced some climate change anxiety.
In recent years, plumes of methane bubbles rising up from what was once dry permafrost have been observed off the Siberian coast.

But their context was unclear. Were they a brand-new greenhouse gas release driven by climate change or were the bubbles long-time fixtures?
Work off the coast of Svalbard provided a welcome bit of relief.

Examination of similar bubble plumes off Svalbard showed that they had been present (at some rate of bubbling) for thousands of years. While estimates of the amount of methane coming out of the East Siberian Sea were surprisingly large, measurements near Svalbard showed that the methane from deeper seafloor seeps gets trapped in the water column and consumed by bacteria before it can reach the atmosphere.

That helped put the Siberian activity in some global context.

A new study led by United States Geological Survey researcher John Pohlman delivers another Svalbard surprise. Pohlman’s team looked at the other side of the ledger: how much carbon is pulled out of the atmosphere by photosynthetic critters at these sites?
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