July 28, 2015
Are We Falling Off the Climate Precipice?
Posted on Dec 19, 2013
By Dahr Jamail, TomDispatch
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.
Square, Site wide
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.
New and Improved Comments