As if the melting methane-packed permafrost and shrinking Arctic ice
sheets weren't enough, NASA scientists have gone and uncovered a brand
new feedback loop that could hasten climate catastrophe. Climate
feedback loops, to the uninitiated, are phenomena that worsen the
warming effect when triggered—which further worsens said phenomena, and
around we go.
The permafrost is probably the gnarliest: there's a
truly stupendous amount of greenhouse gases trapped in the frozen
tundras across Siberia, Alaska, Canada, etc. As the permafrost melts, it
releases those gases into the atmosphere, which warms it up, and melts
more permafrost. If warming keeps apace, permafrost could soon
contribute 35% of worldwide greenhouse gas emissions. That's terrifying.
So is this:
"Researchers have known for years that large amounts of methane are
frozen in Arctic tundra soils and in marine sediments ... But now a
multi-institutional study led by Eric Kort of NASA’s Jet Propulsion
Laboratory has uncovered a surprising and potentially important new
source of methane: the Arctic Ocean itself."
That
emphasis is mine, and a correct reading of the quote will include a
dramatic and cartoony 'duhn-duhn-duhn' sound effect registered
immediately after. And believe you me, it's justified. NASA scientists
say that when they flew research flights over areas in the Arctic Sea
where the ice was breaking up, they encountered higher than usual levels
of methane. They then set out trying to determine where it came from:
By comparing the locations of the enhanced methane levels with airborne measurements of carbon monoxide, water vapor, and ozone, the researchers from six institutions pinpointed a source: the ocean surface, in places where there were cracks and openings in the sea ice cover. The cracks were allowing methane in the top layers of the sea to escape into the atmosphere. The team did not detect enhanced methane levels over areas of solid ice.Kort noted that previous studies had detected high concentrations of methane in Arctic surface waters, but no one had predicted that this dissolved methane would find its way into the overlying atmosphere ... “It’s possible that as large areas of sea ice melt and expose more ocean water, methane production may increase, leading to larger methane emissions,” he said. “While the methane levels we detected weren’t particularly large, the potential source region, the Arctic Ocean, is vast."In other words, cracks in sea ice are allowing methane trapped in surface ocean to escape into the atmosphere. More warming means more cracks, which means more methane (and remember methane is a much more potent heat-trapping gas than carbon), which means more cracks.Further investigation certainly must be done to uncover the true scope of this threat, but it certainly doesn't sound good
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