In addition to the dislocations and changes in standard of living that are likely outcomes of climate change, there are the fundamental limits to industrial civilization imposed by thermodynamics. I hope these issues can be part of the discussion of what kind of future to embrace.
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From Sven E Jorgensen and Yuri M Svirezhev, Towards a Thermodynamic Theory for Ecological Systems, Elsevier, 2004, pages 276-277. [minor grammar edits by dw]
"If we consider the main characteristic features of technological civilisation, we can see that it creates [...] energy and chemical loads. These features are:
(a) the use of the non-biosphere sources of energy (fossil fuels, which are the traces of past biospheres, not replenishable by the current biosphere, and nuclear energy);
(b) technological processes [that] increase concentrations of chemical elements in the biosphere (metallurgy, chemical industry, etc.):
(c) dispersion of chemical elements in comparison with their "biotic" concentrations.
All the above-mentioned processes produce entropy that cannot be 'sucked' out by the biosphere's 'entropy pump'. But since the ecosystem should remain in a dynamic equilibrium with its environment, the entropy production (overproduction) of the ecosystem should be compensated by the outflow of entropy to the environment. This compensation can occur only at the expense of environmental degradation in this, or, maybe, another location, [the degradation being] heat and chemical pollution or [other degradation] caused by mechanical impact on the system. The value of the overproduction (as was shown in Chapter 10) can be used as a criterion for the environmental degradation or as an 'entropy fee', which has to be paid by society (really suffering from the degradation of environment) for the modern industrial technologies. Thus, degradation of the environment is the only way to compensate for the overproduction of entropy. The process of overproduction can be non-homogenous in space and then there is the spatial transportation of entropy. This transportation can be either natural or artificial. The natural process of entropy transportation is realised as the wide spreading of different pollutants by natural agents (wind, rivers, etc.). The artificial process is either a purposeful export of industrial waste to other regions, or the import of low-entropy [material] (for example, fossil fuels) from other regions. So, the main conclusion is:
Sustainable development is possible only locally, and only at the expense of creating 'entropy dumps' elsewhere."
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4 comments:
First of all, there is no recognized law of thermodynamics that governs changes in entropy in non-isolated systems, e.g. the Earth's biosphere. The number of variables is simply too great (at present) to formulate such a law with any degree of certainty. Entropy in a non-isolated system is very much an open question, and the posted article is but ONE view. Thus, we cannot say that thermodynamics imposes a "fundamental limit" on industrial civilization. In any case, the primary pollutant produced by fossil fuel combustion, CO2, IS subject to absorption by the biosphere. And so to assert that "[the compensation in entropy imbalance] can occur only at the expense of environmental degradation" is problematic at best.
Secondly, and I have noted this tendency nearly everywhere on the left in Oregon, we should be more careful about idealism with regard to technological and industrial development.
Could someone define the terms for those of us who are unfamiliar with the concepts being expressed here?
Thermodynamics is the study of the movement of heat. Entropy is basically the amount of disorder in a system. The second law of thermodynamics states that the total amount of entropy in a system won't decrease except by increasing entropy in some other system. The article is arguing that the entropy increases in industrial processes flow into the environment as pollution. The problem is, the second law only governs the movement of entropy in and around isolated systems like air conditioners (meaning systems with a finite number of inputs and outputs). The biosphere is very different, since it has an essentially infinite number of inputs and outputs, and entropy "sinks", i.e. living things, that don't exist in refrigerators or ACs.
Thanks for the comments. The only aspect of the earth system that is open is solar input, which is non-trivial of course. Nevertheless, discarded computers shipped to China, trash barges sent to wherever, are examples of what industrial countries sometimes try to do to export their waste. There is no complete recycling system that I am aware of for the typical complex of industrial products used in a typical city, urban area, or larger area for that matter, unless one wants to think in time frames of thousands of years (for nuclear isotope half-lives for example).
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