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Alliance for Global Sustainability. Mathis Wackernagel: Global Footprint Network Christian Azar: Turning the Tide Dennis Meadows: Limits to Growth The Spanish Pathway Conclusions. Table of Contents.
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Mathis Wackernagel: Global Footprint Network Christian Azar: Turning the Tide Dennis Meadows: Limits to Growth The Spanish Pathway Conclusions Table of Contents
This report contains some material taken from the proceedings of the AGS Conference. Those slides are interspersed with material produced by me. Since the proceedings were only published in PDF format, all material taken from the proceedings has been included in pixel graphics, i.e. by capture and paste. The material pasted from other documents is clearly marked by hyperlinks. The typeset text is all mine. Especially, since the material from the Spanish pathway was not included in the proceedings, that material (or rather, the interpretation thereof) is all mine. Finally and most importantly, the conclusions presented on the last page of this document are not official conclusions reached by the conference, but rather, they are my personal conclusions, for which I carry sole responsibility. Disclaimer
It takes relatively little additional resources to dramatically increase the quality of life of the poor nations. The Good News …
It is steeper, because we live more wastefully. The poor nations use their few resources in an almost optimal fashion. They cannot afford to waste anything. We don’t think much about how we might use our resources more efficiently. Why is the European Gradient Steeper? • We heat our houses to high temperature values, while keeping the windows open. • We buy food that we don’t need. • We maintain secondary homes that we don’t need. • …
The U.S. and the United Arab Emirates consume simply because they can, without increasing their quality of life any further. It is human nature to think first about themselves individually, and only later about the species as a whole. Humans are constantly in competition with each other. They increase their feeling of “self-worth” by taking something away from another human being. Example: Easter Islands. If we want to survive as a species, while keeping up a decent quality of life, we must learn to become … No Strings Attached … not “Berliners,” but “Cubans.”
Becoming “Cubans” won’t happen on its own. If the Cubans were given a choice, they would gladly vote to become the 51st State in the Union … if only they could drive around in these sinfully gorgeous SUVs, heat their homes in the winter to 24oC, while cooling them down in the summer to 18oC. We achieve the transition either by regulations … or the planet will achieve it for us, probably in ways that we won’t like a bit. The Bad News …
Every species outgrows its resources over time. A population of lab rats will stop reproducing only when there is no longer enough food for all of them. Populations are naturally controlled by hunger and disease, not by living standard. Whereas humans individually (on a local scale) are capable of behaving in a civilized way and helping each other, there has been no sign so far that humanity, as a species (on a global scale), behaves any differently from lab rats. More Bad News …
Global Ecological Balance Sheet(in global hectares/person, 2003 data)
Although the EU signed the Kyoto agreement whereas the U.S. did not, their increase in CO2 emissions over time is approximately the same. Switzerland signed the Kyoto agreement. What has Switzerland done since then to actually curb CO2 emissions? Absolutely nothing. We talk a lot … but the CO2 emissions won’t go away by talk alone. As I shall demonstrate, relying on market forces won’t make them go away either. Words and Deeds
The climate seems to exhibit something like a bi-stable behavior with long ice ages (around 100.000 years) interrupted by short interglacial periods (around 10.000 years). This behavior can only be explained by positive feedback loops and nonlinearities. We understand some of the positive feedback loops. We have no clear understanding of what brings the next ice age about (although we have some ideas about it). We have no understanding whatsoever as to what mechanisms end an ice age. Mechanisms for Temperature Changes
A predicted global warming of 3-5 degrees Centigrade within the next 100 years is colossal. The difference between current global annual temperature averages and ice ages averages is only 4oC. If the average temperature rises by another 4oC above current values, the arctic icecap will melt. The melting of the icecap will make the oceans less salty. This could derail the golf stream and bring the next ice age about. Since we don’t really understand yet what we are doing … it might be a good idea not to do it. Global Warming
Using less energy (e.g. by thermally insulating the houses better) is by far the cheapest, i.e., the most cost-effective option. Using other forms of energy is something that we should do, but it won’t solve the problem in the short run. Local decentralized solutions are more easily realizable than global centralized solutions, although the latter may be more cost-effective. Carbon capture is a good technology for the future for global CO2 management. Available Options
“Difficult” Problems Become “Easy” with Greater Time Horizon
Let me concretize the nature of “difficult” problems by means of a simple optimization study using Forrester’s world model. I chose that model over Meadows’ newer world model, because Forrester published his full model in his book World Dynamics, whereas Meadows published only the results of his studies in his book Limits to Growth. The exercise serves to demonstrate why market forces alone are likely to drive us down the path of overshoot and collapse, rather than down the path of a sustainable future. Why are Many Problems “Difficult”?
It turns out that, as the natural resources shrink to a level below approximately 5·1011, this generates a strong damping effect on the population. Simulation Results II The model shows nicely the limits to growth. The population peaks at about the year 2020 with a little over 5 billion people.
Forrester thus proposed to reduce the usage of the natural resources by a factor of 4, starting with the year 1970. This may be just as well. The effect of this modification is approximately the same as saying that more resources are available than anticipated. This is indeed true. Now, the resource exhaustion won’t be effective as a damping factor any longer. 1st Modification
As we are now modifying a parameter, NRUN, this former parameter had now to become a variable. I could have modified the multiplier instead, but the nonlinear function was optically more appealing to me. Program Modification I (I had to extend a few of the function domains to prevent the assert clauses in the Piecewise function from killing the simulation.)
Collapse Simulation Results III
We now want to optimize the consumption of natural resources after the year 1970. To this end, we shall need a performance index. What is good, is a high value of the minimal quality of life after the year 2000 (optimizing the past doesn’t make much sense). What is bad, is a die-off of the population. Accordingly, we modify the program once more. This is all done in the equation window. Optimization
The first two simulations are plagued by massive die-off. The others are fine. Yet, in the short run, those solutions that will give us bad performance (die-off) exhibit the best performance. NRUN2 = 0.25 NRUN2 = 0.5 NRUN2 = 0.75 NRUN2 = 1.0 NRUN2 = 1.5 Simulation Results IV
