millions of years of ice ages, the Arctic has become a vast
repository of fossil carbon.
the millennia, layer after layer of carbon-based biological material
has been locked away in the frozen soil of the Arctic tundras and sea
beds. Some of these stores have simply become entombed within the
ice. Others, already turned to methane through the slow fluxes of
time, underlay the frozen ground and the chilly Arctic sea-bed floor
as a kind of fire ice.
unstable, flammable, and explosive substance called clathrate.
stores themselves are massive — containing between 2,000 to 3,000
billion tons or more of carbon. Likely more than five times the
amount of carbon humans have already emitted into the atmosphere over
the past 150 years. An amount that has already likely locked in about
1.8 C of warming short term and 3.6 C worth of warming long-term.
a thawing Arctic could set off a chain of events leading to far worse
warming to come.
a cold, ice-age world these carbon stores are no threat. Like a
sleeping dragon, they remained dormant in the world’s chill zones —
unable to break the seal of the ice. But in a world that humans are
forcing to rapidly warm through a pace of greenhouse gas emission at
least 6 times faster than at any time in Earth’s billions-years
history, we risk a major release of this monstrous carbon stockpile.
Matter of Methane Feedback
really don’t know how much heat forcing is required to set off a
runaway release of this monstrous pile of carbon. But we’ve already
warmed the world by at least 0.8 degrees Celsius and many Arctic
researchers believe that just 1.5 degrees Celsius global warming is
enough to thaw all the Arctic’s tundra.
a thaw would certainly expose the massive tundra carbon store to the
elements and to
Increasing an already significant release of Arctic carbon and
greatly contributing to the human heating of the Earth’s atmosphere
and oceans through greenhouse gas emissions.
(In a recent article on his Meltfactor blog, Dr. Jason Box questions whether local anomalies in Arctic methane data involve mini methane outbursts set off by human-caused heating. Dr. Box also, appropriately questioned whether such releases were signs of a potential and larger release due to the human heat forcing of the Arctic environment. Dr. Box, in a manner similar to our own investigation of the Arctic Methane Monster, metaphorically labels these outbursts ‘dragon’s breath.’ Image source: Meltfactor.)
the matter of Arctic carbon release is anything but simple or easy to
understand. For a significant portion — possibly as much 1/3 to 1/2
of the Arctic carbon store could release as methane. And methane, on
very short time scales, is a very potent greenhouse gas. Over the
course of 20 years, methane has a global warming potential 86 times
that of a similar volume of CO2. If even a very small portion of the
Arctic carbon store were to release as methane over a relatively
short period — 1, 5, 10 or 50 gigatons out of a total store
measuring in the thousands of gigatons — it could greatly
exaggerate the already powerful human warming underway or, in the
worst case, set off a runaway heating event similar to that of the
great Permian and PETM extinctions.
(Large sea-bed methane release ongoing? The Arctic continues to show a very significant overburden of Methane — hinting at larger releases of methane from the Arctic environment. Last year during October, methane readings over the Gakkel Ridge spiked to 2662 parts per billion — or more than 800 parts per billion above the global average — before diffusing into the atmosphere. The above image shows methane over the same region spiking to over 2,400 parts per billion on September 16 of 2014. Link: Arctic News.)
these studies and instances focus only on subsections of the Arctic.
And, in much the way several blind men investigating the various
parts of an elephant might disagree on the overall shape of the
beast, we have a similar problem with understanding the total shape
of the threat posed by Arctic methane and carbon release.
who has developed various model essays of potential Arctic and sea
bed methane release claims that there is essentially zero cause for
concern for a large-scale methane release this century. A number of
Arctic researchers disagree with the chief of these being Peter
Semiletov and Dr Shakhova who
all seem very concerned about the potential for a large-scale release
soon. A middle ground is populated by a number of researchers
Ruppel and Sue
Natali from the Woods Hole observatory.
These researchers are rationally calling for more data on an issue
that is all-too-poorly understood in the science.
CARVE Finds Models in Disagreement Over Arctic Carbon Release
current lack of broader understanding and scientific consensus on the
issue of potential Arctic and Earth Systems response to a growing
human heating of the atmosphere and ocean was highlighted in
last week’s report by NASA’s CARVE study.
study — aimed at monitoring Arctic Carbon emissions — ran a
number of global climate models to try and determine how much carbon
is currently being released from the Arctic environment. The study
didn’t try to pin down future release scenarios. It just aimed at
trying to establish a base line for emissions as they stand now. An
understanding required to provide any clear assessment of where
Arctic carbon emissions may be going in the future.
researchers plugged the current spotty Arctic carbon emissions data
into 40 global climate models and the models dutifully spit out
results that were all across the board. In essence, the models
confirmed what we risk analysts already knew — there’s not enough
information currently available to provide a clear understanding of
potential Arctic carbon release scenarios much less pin down how much
carbon is currently being emitted.
much carbon is leaving its thawing soil and adding to Earth’s
greenhouse effect? …
new study conducted as part of NASA’s Carbon in Arctic Reservoirs
Vulnerability Experiment (CARVE) shows just how much work still needs
to be done to reach a conclusion on this and other basic questions
about the region where global warming is hitting hardest.
author Josh Fisher of NASA’s Jet Propulsion Laboratory, Pasadena,
California, analyzed 40 computer models of the amounts and flows of
carbon in the Alaskan Arctic and boreal ecosystems. His team found
wide disagreement among the models, highlighting the urgent need for
more measurements from the region…
all knew there were big uncertainties in our understanding, and we
wanted to quantify their extent,” said Fisher. That extent proved
to be greater than almost anyone expected. “The results were
shocking to most people,” he said.
For Rapid Reduction in Greenhouse Gas Emissions Now
(Ocean methane seeps like these recently discovered vents off the US East Coast and those Discovered in the Laptev Sea by the SWERUS C3 expedition are almost always more numerous and energetic than expected — a likely result of increasing human heat forcing. Such releases almost always include destabilized clathrate stores. Image source: Nature-Geoscience.)
will take years for scientists to more certainly pin down the risk
posed by Arctic Carbon and methane release. A risk that now wraps
within it the potential to set off a new Permian type hothouse
extinction during the coming 1 to 3 centuries. A risk that,
altogether, is likely the most dire risk we’ve ever faced as a
such, we can’t wait for absolute certainty on the scope of that
risk. Whether there’s enough sensitivity to set off a large Arctic
carbon release at 1.5 C or 6 C warming is moot — because we know
that continuing to burn fossil fuels eventually gets us there sooner
as we continue to research what may well be the greatest
environmental threat we’ve ever faced it is entirely prudent to
begin a rapid reduction of global carbon emissions with a goal to hit
zero carbon and net negative carbon emissions as soon as possible.
The risks are simply too great to continue to delay action.