The Math Of A Sustainable American Way Of Life… or, How Much Less Do We Need To Consume To Avoid Global Ecosystem Collapse?

This article emerges out of a number I tossed out in a posting on Facebook a day or two ago, suggesting that the average American would need to consume something on the order of 5% of the resources they presently consume (collectively) if their standard of living were to be equalized with the rest of the world’s population without destroying the planet’s ecosystem (i.e., how much less would we need to consume for the rest of the world to be able to consume an amount equal to what we do).
A friend asked me where I got that number from, and I’m somewhat embarassed to admit (since I’m such a data driven person) that I can’t actually recall at this point – I did the math in my head a while ago. I did some research for real numbers, mostly searches and reading on ecological footprint figures, as I vaguely recall basing the calculation on something along those lines; at this point, while the 5% number may actually have been based on some other metric entirely, the footprint metric seems the most reasonable one to use for the purpose of discussion.

A fair amount of reading leads me to believe that the best publicly supported estimates at this point aren’t quite as severe as the 5% number I tossed out – according to and, the average American consumes approximately 5.3x the amount of resources required for sustainability. Therefore, we’re looking to have to consume slightly less than 19% of the resources we currently use in order for the American standard of living to be “sustainable”. Daunting, but not quite as daunting as 5% of the resources. Caveats below, however.
First of all, as noted in many articles, the footprint calculations are conservative — meaning that they clearly underestimate, perhaps significantly, human impact on the overall ecology and thus the amount of resources that can be sustainably extracted to support our standard of living. How much of a “fudge” factor we need to incorporate into these estimates is unclear.
It’s important to note, as well, that it appears that the percentage of the world’s biocapacity devoted to sustaining non-human species under most of these “ecological footprint” measures is minimal… on the order of 12% (meaning humans would reserve 88% of the world’s biocapacity for themselves alone) according to the “A Modest Proposal” article referenced below. Also, that 19% figure does not account for a projected world population increase on the order of 33% above current levels (6.7 billion to 9 billion by 2040), which turns that ~19% of current levels into ~15% (assuming a relatively static US population compared to overall world totals).
Nor do they account for degradation and loss of biocapacity over time, due to global warming or ongoing biological degradation.
Setting aside these caveats, I’d say that a reasonable and cautious estimate for sustainable and equalized world consumption, with a just and fair amount set aside for non-human species and recovery of degraded ecosystems and to account for population increase, is probably around 10% (rather than 5%).
On the other hand, it seems to me, intuitively, based on everything I’m seeing about how rapidly the world’s ecosystem resources are being degraded, and the prospect of global warming affecting biocapacity, etc. that if we really want to be conservative, and have a good margin of error, we should be looking at something below 10%. Maybe not 5% exactly, but not too far from it.
Now, here’s an experiment (and why I mentioned this in the first place): toss this number out — be conservative, pick the 10% figure… hell, pick the 20% figure (with an aside to the effect that it’s probably on the high side of what we should be targeting) — into a group conversation with a bunch of liberal, ecologically conscious Americans and ask what the implications of this are, of the fact that even the most eco-conscious of them is living an unsustainable lifestyle, RIGHT NOW, and watch how rapidly the topic of conversation veers away onto other subjects (we won’t even get into the reaction of other folks). I’ve done this several times, among my peers in Santa Cruz, and the results have been quite instructive.
If we, ourselves, can’t even begin to conceive of how to reduce our impact on the planet to the degree necessary to achieve sustainability, what hope do we have for the rest of the world? Scary thought, eh?
References (all retrieved March 19th, 2009):
Ecological Footprint – article on Sustainable Scale web site
Ecological Footprint Quiz by Redefining Progress
Footprint Network article on WFF Living Planet Report 2004
Footprint Calculator
EarthDay Footprint Calculator
Note: both calculators produced roughly equivalent results in my case (4.7x and 5.1x respectively, mostly due to the extreme number of miles I drive a year, around 36,000, mostly in the form of long distance commutes to client sites).
Culture Change – Overextension: our American way of life is not sustainable
A modest proposal: global rationalization of ecological footprint to eliminate ecological debt
Ask EarthTrends: How much of the world’s resource consumption occurs in rich countries?