What Does Sustainability Mean

= "Growth—either in physical measures like population, energy use, etc., or in economic terms—cannot continue indefinitely in our finite world".

URL = http://physics.ucsd.edu/do-the-math/2011/10/sustainable-means-bunkty-to-me/

Discussion

Tom Murphy:

"Growth—either in physical measures like population, energy use, etc., or in economic terms—cannot continue indefinitely in our finite world. This post rounds out the trilogy.

If we think about the fact that growth must one day end, we realize that an ultimate steady state would tend to reduce income inequalities. Given growth, we have little trouble rationalizing inequality, since those at the bottom have growth opportunity ahead of them. As long as the plight of the poor improves with time, the well-heeled among us can feel justified in living large. But without a growth argument, it would become morally awkward to perpetuate the inequality of two people contributing comparable time and energy to humanity’s steady-state upkeep.

Our dream is that the poor of the world can improve their standard of living toward first-world norms. The U.S. uses about 25% of the world’s annual energy resource (which I will use as a proxy for standard of living) while harboring about 5% of the population. Thus the average U.S. citizen uses energy at five times the rate of the average global citizen. For everyone to get where we are today in the U.S. would require a five-fold increase in the total energy expenditure of the planet. Make that 7-fold allowing the population to swell to 10 billion. And even that requires a freeze in growth at the top end (the U.S.). Since that’s not about to happen—at least not voluntarily—we should call it a ten-fold increase for everyone to get what they want.

If we are not sustainable today, how could we possibly achieve sustainability under the burden of a ten-fold increase in scale?

You may object that Americans don’t eat five times more food than the average Earthling today. True enough, but we eat a meat-rich diet that consumes much more land, grain, and energy than would a simpler diet by something close to that same factor. You might also object that Americans use energy at an obscene rate, and that this should not be the goal for the rest of the world. " (http://physics.ucsd.edu/do-the-math/2011/10/sustainable-means-bunkty-to-me/)

More Information

Recommended in: John Thackara's Thermodynamic Bibliography