Friday, 27 December 2013

Considering Extinction

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.
Read  the rest here:  popularresistance.org