Considering Extinction: Are We Falling Off The Climate
Precipice?
By Dahr Jamail, www.commondreams.org
I grew up planning for my future, wondering which college I
would attend, what to study, and later on, where to work, which articles to
write, what my next book might be, how to pay a mortgage, and which
mountaineering trip I might like to take next.
Now, I wonder about the future of our planet. During a
recent visit with my eight-year-old niece and 10- and 12-year-old nephews, I
stopped myself from asking them what they wanted to do when they grew up, or
any of the future-oriented questions I used to ask myself. I did so because the
reality of their generation may be that questions like where they will work
could be replaced by: Where will they get their fresh water? What food will be
available? And what parts of their country and the rest of the world will still
be habitable?
“We’ve never been
here as a species and the implications are truly dire and profound for our
species and the rest of the living planet.” –Prof. Guy McPherson, University of
Arizona
The reason, of course, is climate change — and just how bad
it might be came home to me in the summer of 2010. I was climbing Mount Rainier in Washington
State, taking the same route I had used in a 1994 ascent. Instead of experiencing the metal tips of the
crampons attached to my boots crunching into the ice of a glacier, I was aware
that, at high altitudes, they were still scraping against exposed volcanic
rock. In the pre-dawn night, sparks shot from my steps.
The route had changed dramatically enough to stun me. I
paused at one point to glance down the steep cliffs at a glacier bathed in soft
moonlight 100 meters below. It took my breath away when I realized that I was
looking at what was left of the enormous glacier I’d climbed in 1994, the one
that — right at this spot — had left those crampons crunching on ice. I stopped
in my tracks, breathing the rarefied air of such altitudes, my mind working
hard to grasp the climate-change-induced drama that had unfolded since I was
last at that spot.
I haven’t returned to Mount Rainier to see just how much
further that glacier has receded in the last few years, but recently I went on
a search to find out just how bad it might turn out to be. I discovered a set of
perfectly serious scientists — not the majority of all climate scientists by
any means, but thoughtful outliers — who suggest that it isn’t just really,
really bad; it’s catastrophic. Some of
them even think that, if the record ongoing releases of carbon dioxide into the
atmosphere, thanks to the burning of fossil fuels, are aided and abetted by
massive releases of methane, an even more powerful greenhouse gas, life as we
humans have known it might be at an end on this planet. They fear that we may
be at — and over — a climate change precipice hair-raisingly quickly.
Mind you, the more conservative climate science types,
represented by the prestigious Intergovernmental Panel on Climate Change
(IPCC), paint scenarios that are only modestly less hair-raising, but let’s
spend a little time, as I’ve done, with what might be called scientists at the
edge and hear just what they have to say.
“We’ve Never Been
Here as a Species”
“We as a species have
never experienced 400 parts per million of carbon dioxide in the atmosphere,”
Guy McPherson, professor emeritus of evolutionary biology, natural resources,
and ecology at the University of Arizona and a climate change expert of 25
years, told me. “We’ve never been on a planet with no Arctic ice, and we will
hit the average of 400 ppm… within the next couple of years. At that time,
we’ll also see the loss of Arctic ice in the summers… This planet has not
experienced an ice-free Arctic for at least the last three million years.”
For the uninitiated, in the simplest terms, here’s what an
ice-free Arctic would mean when it comes to heating the planet: minus the
reflective ice cover on Arctic waters, solar radiation would be absorbed, not
reflected, by the Arctic Ocean. That
would heat those waters, and hence the planet, further. This effect has the
potential to change global weather patterns, vary the flow of winds, and even
someday possibly alter the position of the jet stream. Polar jet streams are
fast flowing rivers of wind positioned high in the Earth’s atmosphere that push
cold and warm air masses around, playing a critical role in determining the
weather of our planet.
McPherson, who maintains the blog Nature Bats Last, added,
“We’ve never been here as a species and the implications are truly dire and
profound for our species and the rest of the living planet.”
While his perspective is more extreme than that of the
mainstream scientific community, which sees true disaster many decades into our
future, he’s far from the only scientist expressing such concerns. Professor
Peter Wadhams, a leading Arctic expert at Cambridge University, has been
measuring Arctic ice for 40 years, and his findings underscore McPherson’s
fears. “The fall-off in ice volume is so
fast it is going to bring us to zero very quickly,” Wadhams told a reporter.
According to current data, he estimates “with 95% confidence” that the Arctic
will have completely ice-free summers by 2018.
(U.S. Navy researchers have predicted an ice-free Arctic even earlier —
by 2016.)
British scientist John Nissen, chairman of the Arctic
Methane Emergency Group (of which Wadhams is a member), suggests that if the
summer sea ice loss passes “the point of no return,” and “catastrophic Arctic
methane feedbacks” kick in, we’ll be in an “instant planetary emergency.”
“Economic growth is
the biggest destroyer of the ecology… Those people who think you can have a
growing economy and a healthy environment are wrong. If we don’t reduce our
numbers, nature will do it for us.” –Neil Dawe, biologist
McPherson, Wadham, and Nissen represent just the tip of a
melting iceberg of scientists who are now warning us about looming disaster,
especially involving Arctic methane releases. In the atmosphere, methane is a
greenhouse gas that, on a relatively short-term time scale, is far more destructive
than carbon dioxide (CO2). It is 23
times as powerful as CO2 per molecule on a 100-year timescale, 105 times more
potent when it comes to heating the planet on a 20-year timescale — and the
Arctic permafrost, onshore and off, is packed with the stuff. “The seabed,” says Wadham, “is offshore
permafrost, but is now warming and melting. We are now seeing great plumes of
methane bubbling up in the Siberian Sea… millions of square miles where methane
cover is being released.”
According to a study just published in Nature Geoscience,
twice as much methane as previously thought is being released from the East
Siberian Arctic Shelf, a two million square kilometer area off the coast of
Northern Siberia. Its researchers found that at least 17 teragrams (one million
tons) of methane are being released into the atmosphere each year, whereas a
2010 study had found only seven teragrams heading into the atmosphere.
The day after Nature Geoscience released its study, a group
of scientists from Harvard and other leading academic institutions published a
report in the Proceedings of the National Academy of Sciences showing that the
amount of methane being emitted in the U.S. both from oil and agricultural
operations could be 50% greater than previous estimates and 1.5 times higher
than estimates of the Environmental Protection Agency.
How serious is the potential global methane build-up? Not
all scientists think it’s an immediate threat or even the major threat we face,
but Ira Leifer, an atmospheric and marine scientist at the University of
California, Santa Barbara, and one of the authors of the recent Arctic Methane
study pointed out to me that “the Permian mass extinction that occurred 250
million years ago is related to methane and thought to be the key to what caused
the extinction of most species on the planet.” In that extinction episode, it
is estimated that 95% of all species were wiped out.
Also known as “The Great Dying,” it was triggered by a
massive lava flow in an area of Siberia that led to an increase in global
temperatures of six degrees Celsius. That, in turn, caused the melting of
frozen methane deposits under the seas.
Released into the atmosphere, it caused temperatures to skyrocket
further. All of this occurred over a period of approximately 80,000 years.
We are currently in the midst of what scientists consider
the sixth mass extinction in planetary history, with between 150 and 200
species going extinct daily, a pace 1,000 times greater than the “natural” or
“background” extinction rate. This event may already be comparable to, or even
exceed, both the speed and intensity of the Permian mass extinction. The
difference being that ours is human caused, isn’t going to take 80,000 years,
has so far lasted just a few centuries, and is now gaining speed in a
non-linear fashion.
It is possible that, on top of the vast quantities of carbon
dioxide from fossil fuels that continue to enter the atmosphere in record
amounts yearly, an increased release of methane could signal the beginning of
the sort of process that led to the Great Dying. Some scientists fear that the
situation is already so serious and so many self-reinforcing feedback loops are
already in play that we are in the process of causing our own extinction. Worse
yet, some are convinced that it could happen far more quickly than generally
believed possible — even in the course of just the next few decades.
The Sleeping Giant Stirs
According to a NASA research report, “Is a Sleeping Climate
Giant Stirring in the Arctic?”: “Over hundreds of millennia, Arctic permafrost
soils have accumulated vast stores of organic carbon — an estimated 1,400 to
1,850 petagrams of it (a petagram is 2.2 trillion pounds, or 1 billion metric
tons). That’s about half of all the estimated organic carbon stored in Earth’s
soils. In comparison, about 350 petagrams of carbon have been emitted from all
fossil-fuel combustion and human activities since 1850. Most of this carbon is
located in thaw-vulnerable top soils within 10 feet (3 meters) of the surface.”
NASA scientists, along with others, are learning that the
Arctic permafrost — and its stored carbon — may not be as permanently frosted
as its name implies. Research scientist
Charles Miller of NASA’s Jet Propulsion Laboratory is the principal
investigator of the Carbon in Arctic Reservoirs Vulnerability Experiment
(CARVE), a five-year NASA-led field campaign to study how climate change is
affecting the Arctic’s carbon cycle. He told NASA, “Permafrost soils are
warming even faster than Arctic air temperatures — as much as 2.7 to 4.5
degrees Fahrenheit (1.5 to 2.5 degrees Celsius) in just the past 30 years. As
heat from Earth’s surface penetrates into permafrost, it threatens to mobilize
these organic carbon reservoirs and release them into the atmosphere as carbon
dioxide and methane, upsetting the Arctic’s carbon balance and greatly
exacerbating global warming.”
He fears the potential results should a full-scale
permafrost melt take place. As he points out, “Changes in climate may trigger
transformations that are simply not reversible within our lifetimes,
potentially causing rapid changes in the Earth system that will require
adaptations by people and ecosystems.”
The recent NASA study highlights the discovery of active and
growing methane vents up to 150 kilometers across. A scientist on a research
ship in the area described this as a bubbling as far as the eye can see in
which the seawater looks like a vast pool of seltzer. Between the summers of
2010 and 2011, in fact, scientists found that in the course of a year methane vents
only 30 centimeters across had grown a kilometer wide, a 3,333% increase and an
example of the non-linear rapidity with which parts of the planet are
responding to climate disruption.
Miller revealed another alarming finding: “Some of the
methane and carbon dioxide concentrations we’ve measured have been large, and
we’re seeing very different patterns from what models suggest,” he said of some
of CARVE’s earlier findings. “We saw large, regional-scale episodic bursts of
higher than normal carbon dioxide and methane in interior Alaska and across the
North Slope during the spring thaw, and they lasted until after the fall
refreeze. To cite another example, in July 2012 we saw methane levels over
swamps in the Innoko Wilderness that were 650 parts per billion higher than
normal background levels. That’s similar to what you might find in a large
city.”
Moving beneath the Arctic Ocean where methane hydrates —
often described as methane gas surrounded by ice — exist, a March 2010 report
in Science indicated that these cumulatively contain the equivalent of
1,000-10,000 gigatons of carbon. Compare this total to the 240 gigatons of
carbon humanity has emitted into the atmosphere since the industrial revolution
began.
A study published in the prestigious journal Nature this
July suggested that a 50-gigaton “burp” of methane from thawing Arctic
permafrost beneath the East Siberian sea is “highly possible at anytime.” That
would be the equivalent of at least 1,000 gigatons of carbon dioxide.
Even the relatively staid IPCC has warned of such a
scenario: “The possibility of abrupt climate change and/or abrupt changes in
the earth system triggered by climate change, with potentially catastrophic
consequences, cannot be ruled out. Positive feedback from warming may cause the
release of carbon or methane from the terrestrial biosphere and oceans.”
In the last two centuries, the amount of methane in the
atmosphere has increased from 0.7 parts per million to 1.7 parts per million.
The introduction of methane in such quantities into the atmosphere may, some
climate scientists fear, make increases in the global temperature of four to
six degrees Celsius inevitable.
The ability of the human psyche to take in and grasp such
information is being tested. And while that is happening, yet more data
continues to pour in — and the news is not good.
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