Friday, July 31, 2015

Human Domination of the Biosphere: Rapid discharge of the earth-space battery foretells the future of humankind

Original essay here.
Chris Harries, a follower of this blog, has found an amazing pdf file on XRayMike’s blog that is so amazing, and explains civilisation’s predicaments so well, I just had to write it up for you all to share around. I think that the concept of the Earth as a chemical battery is simply stunning…….. the importance of this paper, I think, is epic.
The paper, written by John R. Schramskia, David K. Gattiea , and James H. Brown begins with clarity…
Earth is a chemical battery where, over evolutionary time with a trickle-charge of photosynthesis using solar energy, billions of tons of living biomass were stored in forests and other ecosystems and in vast reserves of fossil fuels. In just the last few hundred years, humans extracted exploitable energy from these living and fossilized biomass fuels to build the modern industrial-technological-informational economy, to grow our population to more than 7 billion, and to transform the biogeochemical cycles and biodiversity of the earth. This rapid discharge of the earth’s store of organic energy fuels the human domination of the biosphere, including conversion of natural habitats to agricultural fields and the resulting loss of native species, emission of carbon dioxide and the resulting climate and sea level change, and use of supplemental nuclear, hydro, wind, and solar energy sources. The laws of thermodynamics governing the trickle-charge and rapid discharge of the earth’s battery are universal and absolute; the earth is only temporarily poised a quantifiable distance from the thermodynamic equilibrium of outer space. Although this distance from equilibrium is comprised of all energy types, most critical for humans is the store of living biomass. With the rapid depletion of this chemical energy, the earth is shifting back toward the inhospitable equilibrium of outer space with fundamental ramifications for the biosphere and humanity. Because there is no substitute or replacement energy for living biomass, the remaining distance from equilibrium that will be required to support human life is unknown.
To illustrate this stunning concept of the Earth as a battery, this clever illustration is used:
Fig1
That just makes so much sense, and makes such mockery of those who believe ‘innovation’ can replace this extraordinary system.
It took hundreds of millions of years for photosynthetic plants to trickle-charge the battery, gradually converting diffuse low-quality solar energy to high-quality chemical energy stored temporarily in the form of living biomass and more lastingly in the form of fossil fuels: oil, gas, and coal. In just the last few centuries—an evolutionary blink of an eye—human energy use to fuel the rise of civilization and the modern industrial-technological-informational society has discharged the earth-space battery
So then, how long have we got before the battery’s flat?
The laws of thermodynamics dictate that the difference in rate and timescale between the slow trickle-charge and rapid depletion is unsustainable. The current massive discharge is rapidly driving the earth from a biosphere teeming with life and supporting a highly developed human civilization toward a barren moonscape.
The truly surprising thing is how much I’ve been feeling this was the case, and for how long…..  the ever lowering ERoEI of the energy sources we insist on using are merely signal of entropy, and it doesn’t matter how clever we are, or how innovative, entropy rules.  People with green dreams of renewables powered EVs and houses and businesses simply do not understand entropy.
Energy in Physics and Biology
The laws of thermodynamics are incontrovertible; they have inescapable ramifications for the future of the biosphere and humankind. We begin by explaining the thermodynamic concepts necessary to understand the energetics of the biosphere and humans within the earth-space system. The laws of thermodynamics and the many forms of energy can be difficult for non-experts. However, the earth’s flows and stores of energy can be explained in straightforward terms to understand why the biosphere and human civilization are in energy imbalance. These physical laws are universal and absolute, they apply to all human activities, and they are the universal key to sustainability
The Paradigm of the Earth-Space Battery
By definition, the quantity of chemical energy concentrated in the carbon stores of planet Earth (positive cathode) represents the distance from the harsh thermodynamic equilibrium of nearby outer space (negative anode). This energy gradient sustains the biosphere and human life. It can be modeled as a once-charged battery. This earth-space chemical battery (Fig. 1) trickle charged very slowly over 4.5 billion years of solar influx and accumulation of living biomass and fossil fuels. It is now discharging rapidly due to human activities. As we burn organic chemical energy, we generate work to grow our population and economy. In the process, the high-quality chemical energy is transformed into heat and lost from the planet by radiation into outer space. The flow of energy from cathode to anode is moving the planet rapidly and irrevocably closer to the sterile chemical equilibrium of space
Fig2
Fig. 2 depicts the earth’s primary higher-quality chemical and nuclear energy storages as their respective distances from the equilibrium of outer space. We follow the energy industry in focusing on the higher-quality pools and using “recoverable energy” as our point of reference, because many deposits of fossil fuels and nuclear ores are dispersed or inaccessible and cannot be currently harvested to yield net energy gain and economic profit (4). The very large lower-quality pools of organic energy including carbon compounds in soils and oceanic sediments (5, 6) are not shown, but these are not currently economically extractable and usable, so they are typically not included in either recoverable or nonrecoverable categories. Although the energy gradients attributed to geothermal cooling, ocean thermal gradients, greenhouse air temperatures, etc., contribute to Earth’s thermodynamic distance from the equilibrium of space, they are also not included as they are not chemical energies and presumably would still exist in some form on a planet devoid of living things, including humans. Fig. 2 shows that humans are currently discharging all of the recoverable stores of organic chemical energy to the anode of the earth-space battery as heat.
Most people who argue about the viability of their [insert favorite technology] only see that viability in terms of money.  Energy, to most people is such a nebulous concept that they do not see the failures of their techno Utopian solutions…….
Fig3
Living Biomass Is Depleting Rapidly
At the time of the Roman Empire and the birth of Christ, the earth contained ∼1,000 billion tons of carbon in living biomass (10), equivalent to 35 ZJ of chemical energy, mostly in the form of trees in forests. In just the last 2,000 y, humans have reduced this by about 45% to ∼550 billion tons of carbon in biomass, equivalent to 19.2 ZJ. The loss has accelerated over time, with 11% depleted just since 1900 (Fig. 3) (11, 12). Over recent years, on average, we are harvesting—and releasing as heat and carbon dioxide—the remaining 550 billion tons of carbon in living biomass at a net rate of ∼1.5 billion tons carbon per year (13, 14). The cause and measurement of biomass depletion are complicated issues, and the numbers are almost constantly being reevaluated (14). The depletion is due primarily to changes in land use, including deforestation, desertification, and conversion of vegetated landscapes into barren surfaces, but also secondarily to other causes such as pollution and unsustainable forestry and fisheries. Although the above quantitative estimates have considerable uncertainty, the overall trend and magnitude are inescapable facts with dire thermodynamic consequences.
The Dominant Role of Humans Homo sapiens Is a Unique Species.
The history of humankind—starting with huntergatherers, who learned to obtain useful heat energy by burning wood and dung, and continuing to contemporary humans, who apply the latest technologies, such as fracking, solar panels, and wind turbines—is one of innovating to use all economically exploitable energy sources at an ever increasing rate (12, 15). Together, the biological imperative of the Malthusian-Darwinian dynamic to use all available resources and the social imperative to innovate and improve human welfare have resulted in at least 10,000 years of virtually uninterrupted population and economic growth: from a few million hunter-gatherers to more than 7 billion modern humans and from a subsistence economy based on sustainable use of plants and animals (i.e., in equilibrium with photosynthetic energy production) to the modern industrial-technological-informational economy (i.e., out of equilibrium due to the unsustainable unidirectional discharge of the biomass battery).
Fig. 4 depicts the multiplier effect of two large numbers that determine the rapid discharge rate of the earth‐space battery. Energy use per person multiplied by population gives total global energy consumption by humans. According to British Petroleum’s numbers (16), which most experts accept, in 2013, average per capita energy use was 74.6 × 109 J/person per year (equivalent to ∼2,370 W if plotted in green in Fig. 4). Multiplying this by the world population of 7.1 billion in 2013 gives a total consumption of ∼0.53 ZJ/y (equivalent to 16.8 TW if plotted in red in Fig. 4), which is greater than 1% of the total recoverable fossil fuel energy stored in the planet (i.e., 0.53 ZJ/40 ZJ = 1.3%). As time progresses, the population increases, and the economy grows, the outcome of multiplying these two very large numbers is that the total rate of global energy consumption is growing at a near-exponential rate.
fig4
ANY follower of this blog should recognise the peak in the green line as a sure sign of Limits to Growth…. while everything else – population and energy consumption – is skyrocketing exponentially, fooling the techno Utopians into a feeling of security that’s equivalent to what one might feel in their nice new modern car on its way to a fatal accident with no survivors……. everything is going just fine, until it isn’t.
Ironically, powerful political and market forces, rather than acting to conserve the remaining charge in the battery, actually push in the opposite direction, because the pervasive efforts to increase economic growth will require increased energy consumption (4, 8). Much of the above information has been presented elsewhere, but in different forms (e.g., in the references cited). Our synthesis differs from most of these treatments in two respects: (i) it introduces the paradigm of the earth‐space battery to provide a new perspective, and (ii) it emphasizes the critical importance of living biomass for global sustainability of both the biosphere and human civilization.
Humans and Phytomass
We can be more quantitative and put this into context by introducing a new sustainability metric Ω Ω = P BN [1] which purposefully combines perhaps the two critical variables affecting the energy status of the planet: total phytomass and human population. Eq. 1 accomplishes this combination by dividing the stored phytomass chemical energy P (in joules) by the energy needed to feed the global population for 1 y (joules per year; Fig. 5). The denominator represents the basic (metabolic) energy need of the human population; it is obtained by multiplying the global population N by their per capita metabolic needs for 1 y (B = 3.06 × 109 joules/person·per year as calculated from an 8.4 ×106 joules/person·day diet). The simple expression for Ω gives the number of years at current rates of consumption that the global phytomass storage could feed the human race. By making the conservative but totally unrealistic assumption that all phytomass could be harvested to feed humans (i.e., all of it is edible), we get an absolute maximum estimate of the number of years of food remaining for humankind. Fig. 5 shows that over the years 0–2000, Ω has decreased predictably and dramatically from 67,000 to 1,029 y (for example, in the year 2000, P = 19.3 × 1021 joules, B = 3.06 × 109 joules/person·per year, and N = 6.13 × 109 persons; thus, Ω =1,029 y). In just 2,000 y, our single species has reduced Ω by 98.5%. The above is a drastic underestimate for four reasons. First, we obviously cannot consume all phytomass stores for food; the preponderance of phytomass runs the biosphere. Second, basing our estimate on human biological metabolism does not include that high rate of extrametabolic energy expenditure currently being used to feed the population and fuel the economy. Third, the above estimate does not account that both the global human population and the per-capita rate of energy use are not constant, but increasing at near-exponential rates. We do not attempt to extrapolate to predict the future trajectories, which must ultimately turn downward as essential energy stocks are depleted. Finally, we emphasize that not only has the global store of phytomass energy decreased rapidly, but more importantly human dominance over the remaining portion has also increased rapidly. Long before the hypothetical deadline when the global phytomass store is completely exhausted, the energetics of the biosphere and all its inhabitant species will have been drastically altered, with profound changes in biogeochemical function and remaining biodiversity. The very conservative Ω index shows how rapidly land use changes, NPP appropriation, pollution, and other activities are depleting phytomass stores to fuel the current near-exponential trajectories of population and economic growth. Because the Ω index is conservative, it also emphasizes how very little time is left to make changes and achieve a sustainable future for the biosphere and humanity. We are already firmly within the zone of scientific uncertainty where some perturbation could trigger a catastrophic state shift in the biosphere and in the human population and economy (31). As we rapidly approach the chemical equilibrium of outer space, the laws of thermodynamics offer little room for negotiation.
THIS, is the really scary bit………..  collapse, anyone?
fig5
Discussion
The trajectory of Ω shown in Fig. 5 has at least three implications for the future of humankind. First, there is no reason to expect a different trajectory in the near future. Something like the present level of biomass energy destruction will be required to sustain the present global population with its fossil fuel‐subsidized food production and economy. Second, as the earth‐space battery is being discharged ever faster (Fig. 3) to support an ever larger population, the capacity to buffer changes will diminish and the remaining energy gradients will experience increasing perturbations. As more people depend on fewer available energy options, their standard of living and very survival will become increasingly vulnerable to fluctuations, such as droughts, disease epidemics, social unrest, and warfare. Third, there is considerable uncertainty in how the biosphere will function as Ω decreases from the present Ω = ∼1,029 y into an uncharted thermodynamic operating region. The global biosphere, human population, and economy will obviously crash long before Ω = 1 y. If H. sapiens does not go extinct, the human population will decline drastically as we will be forced to return to making a living as hunter‐ gatherers or simple horticulturalists.
The laws of thermodynamics take no prisoners. Equilibrium is inhospitable, sterile, and final.  I just wish we could get through to the people running the planet.  To say this paper blew me away is the understatement of the year, and parsing the ‘good bits’ for this post doesn’t really do it justice.  It needs to be read at least twice in fact, and if you can handle the weight, I’d urge you to read the entire thing at its source https://collapseofindustrialcivilization.files.wordpress.com/2015/07/pnas-2015-schramski-1508353112.pdf
How many of us will “return to making a living as hunter‐ gatherers or simple horticulturalists” I wonder……. We are fast running out of time.

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