Critics, ourselves included, like to sneer at changing light-bulbs, but when light-bulb-changing reaches millions of homes and businesses, that strategy takes giant coal plants off line. What became clear in our years of research into The Biochar Solution, it is that each one of us has a much larger effect on global climate than most of us imagine.
One day in the winter of 1961, exactly 50 years ago, Edward Lorenz was working on an ancient 8-bit computer at MIT trying to understand weather patterns. When he arrived at work that morning, he decided to take a shortcut on his simulation and rather than start from the beginning of the run, he typed in the numbers from a previous point. He walked down the hall for his morning coffee and left the dot matrix printer to re-plot the graph. As he sipped his coffee, a new branch of mathematics, chaos theory, was born.
When Lorenz walked back to his office and looked at the printout, what he saw was something odd. Instead of the same weather pattern as before, the computer had created something new. The repeat pattern started at the same point and followed the previous pattern closely for a short time, but then began to diverge. It continued to diverge until all resemblance to the original sequence disappeared. Lorenz could have assumed something was wrong with his computer, or his program, but he guessed, correctly, that he had stumbled upon something more profound.
Lorenz’s diverging pattern was caused by the significant difference between the six-decimal numbers used by his computer (ie.:.506127) and the rounded-off three-decimal numbers appearing on the printout from which he had re-keyed (ie.:.506). When he typed in the shorter number, he could assume that one part in ten thousand, or a million, would be inconsequential. After all, in numbers referring to windspeed, one part in ten thousand represents only an imperceptible puff of wind, not an entire weather system. But as the difference propagated itself in equation after equation, the entire weather of the earth changed. Lorenz named the phenomenon the “butterfly effect” — because it now seemed that a butterfly stirring the springtime air in Peking could transform the course of summer storms in New York.
Lorenz reasoned that sensitivity to initial conditions was no accident, but is necessary to all natural systems. The influence of small perturbations is what endows larger patterns with such rich variety. It is what gives weather its unpredictability.
There are four parts of the carbon cycle (or the N cycle or the K cycle, whatever you want to look at). Earth (both living topsoil and deep geological reservoirs, including fossil sunlight), Air (the atmosphere), Fire (life in all its forms), and Water (especially the oceans). Labile carbon cycles through these four reservoirs on periods as short as 12 to 15 years on average, but longer for deep earth and oceans. Recalcitrant carbon (biochar or terra preta) cycles through on millennial time scales. Any labile carbon that can be diverted to the recalcitrant cycle can starve the atmosphere and oceans of carbon in the near term -- decades to centuries.
We sometimes wonder why the fungi and bacteria we evolved from wanted us to be here. We can assume that when they made a decision to branch off into plant forms, they needed the stable photosynthetic process to further their exchanges and increase their scope and diversity -- anaerobic vs aerobic, for instance. Likewise, animals gave them a greater range, by pollinating and transporting easily over greater distances, and by complex guts and manures that refined their cuisine with inordinate elegance. So why humans? As we ponder this, what we've come to appreciate is that we provide disturbance. Disturbance in ecosystems increases biodiversity. That is our gift to our bacterial forebears, who still course through our bloodstreams and organs and make up some tiny fraction of our weight. We give them disturbance.
Perhaps they did not anticipate just how much disturbance we two-leggeds are capable of. Or maybe they did.
We took 500 million years of sunlight stored in carbon form and moved it from the Earth to the Air. The Air said, whoa, wait, too much for me, and passed it to Water. Every time a plow cut a field in Sumer, or a Ming dynasty farmer stuck a stick in the ground and diverted water for irrigation, carbon went from dirt to sky to ocean. Agriculture is 40% of greenhouse emissions, but that reckoning is flawed, because it mostly just accounts for the tractors, rice paddies and cow flatulence, not the off-gassing of bared soils. Land disturbance; that is what the two-leggeds do best.
There was a very excellent paper just recently published: Dull, Robert A. , Nevle, Richard J. , Woods, William I. , Bird, Dennis K. , Avnery, Shiri and Denevan, William M. 'The Columbian Encounter and the Little Ice Age: Abrupt Land Use Change, Fire, and Greenhouse Forcing', Annals of the Association of American Geographers, 01 September 2010. The implications are really important. Dull, et al, argue that the re-growth of Neotropical forests following the Columbian encounter led to terrestrial biospheric carbon sequestration on the order of 2 to 5 GtC, thereby contributing to the well-documented decrease in atmospheric C recorded in Antarctic ice cores from about 1500 through 1750 AD (or CE for Buddhists and pagans) previously ascribed to the Columbian encounter by William Ruddiman. Decoding that: When European disease and slavery swept the Americas, so much land was released, much of it with millennial build-up of fertile terra preta, that the trees and vines and rainforests that covered everything took so much carbon away from the cycle that atmospheric C plummeted and Europe literally froze. The Swedes invaded Denmark. Louis XIV put down parquet in the palace at Versailles. Hans Brinker won his silver skates on the frozen canals.
While the paper does not extend to the Medieval Maximum, from charcoal in lake bed studies it documents increased biomass burning and deforestation during agricultural and population expansion in the Neotropics from 2500 to 500 years BP, which would correspond with atmospheric carbon loading and global warming 1100 to 650 years BP. Decoding that: During the rise of the Classic Maya in the Yucatan, the Great White Cities witnessed by Orellana in the first transit of the Amazon, the vast palisade cities along the Mississippi encountered by DeSoto, and trade centers like Cahokia and Teotihuacan, so much carbon was released from forest and field that the atmosphere loaded and the northern hemisphere heated. At the same time there was desertification in N. Africa, driving the Moors into Spain.
Besides hinting at a human-Gaian umbilical far more reciprocating than imagined, what this shows is that the potential exists to return us to pre-Anthrocene concentrations of atmospheric C by reforestation and terrestrial carbon loading, assuming we are not thwarted by Jevon's Paradox and political inertia but also bring down emissions that currently exceed biospheric sequestration by 3.2 GtC/y (although to save the coral reefs, we need to also decarbonize the oceans and that means much more than 3.2 GtC/yr).
In The Biochar Solution we describe the various approaches and compare them in terms of potential for gigaton sequestration on decadal time scales. Jim Bruges does this in his book, The Biochar Debate, also. The main carbon farming advocates (Lal, Ingham, Yeomans) put the organic/holistic farming potential at 1 GtC/y. Biochar advocates (Lehmann, Larson) give a best guess of 4-10 GtC/y for biochar in all its forms. After delving into the Pioneer/Alford Forest model for mixed age/mixed species management, optimizing for ecosystem services and biodiversity but employing step harvest patch disturbance, we put the forestry component at perhaps 40 GtC/y, clearly the dominant wedge.
Recently DemocracyNow! profiled a boy from South Africa who started planting trees at age 9 and organized his classmates to plant a million trees. In our book that is the strategy we talked about: youth tree-planting competitions.
But the catch is that long before we get to 40 GtC/y, we run out of available land. And this, also, is where the versatility of biochar comes into play. We have a chapter about how we can re-green the deserts, much in the way Geoff Lawton is working in Jordan and the Middle East. The Sahara Forest. The Gobi Forest. The Sonoran Forest.
The lifestyles of the pre-Conquest Americans, during the centuries they were clearing land for their cities, likely contributed to pushing the Moors out of North Africa and into the Iberian Peninsula. It was ironic that to expel the invaders the medieval Spanish developed the tools and tactics (such as naval ships, the Andalusian horse and the cavalry charge) that then allowed them to conquer the vastly larger armies of the Americas.
How finely tuned is the human relationship to the climate? What hand might social convention among Paleolithic societies have had in creating Holocene stability? These are large questions we are only just beginning to know enough to ask. Perhaps we will be around long enough to answer them.
Next: Cool food, cool fuel, cool climate.