08/23/2010 03:23 pm ET | Updated May 25, 2011

Oops! Our Planetary eco-Checkbook Bounced Over Weekend

Dear Reader,

I regret to inform you that while you were out enjoying yourself this past weekend, your account became overdrawn. Yes, you. All of us, in fact.

The folks at Global Footprint Network have determined that August 21st was this year's Earth Overshoot Day. That is the point in the year, by which we will have consumed all the resources that the planet can sustainably generate.

"Once we pass this day, humanity will have demanded all the ecological services - from filtering CO2 to producing the raw materials for food - that nature can provide this year. From that point until the end of the year, we meet our ecological demand by liquidating resource stocks and accumulating carbon dioxide in the atmosphere."

In a way, it's a bit like finding out on August 21st that you're not going to get another paycheck until next New Year's Day. How would you deal with that? Your choices become: consume nothing until then, or start selling off your assets or borrowing off your credit cards. But if we borrow, in this scenario, we are borrowing from future generations, with interest rates that might be too high to pay back.

Earth Overshoot Day is computed as the World's Bio-capacity divided by the World Ecological Footprint multiplied by 365 days in a year. That means that this year the planet needs another four months and ten days to re-grow, re-seed, re-spawn, absorb, catch up, filter, purify and heal from what we have asked of it in the previous 7.7 months, just to end up no worse than it was at the beginning of the year.

Another way is looking at this is to say that it would take 1.4 Planet Earths to provide the ecological capacity that we are asking of our one and only planet. That is an overall average for the planet. Some countries are using far more, others far less. The US for example, consumes at a rate that would require five Planet Earths to sustain, by far more than any other country. The UK requires 3.4, South Africa 1.7, China 1.0 and India 0.4. It should be noted that these last two very populous countries, which are largely responsible for the overall rate of only 1.4, are increasing their consumption patterns very rapidly, emulating the US, as global corporations are encouraging them to do. Of all the factors that comprise the World Ecological Footprint including: built up land, forest land, fishing grounds, grazing land, cropland, and carbon footprint, carbon footprint is increasing far faster than all the others.

This situation points very clearly to the very essence of what sustainability is. Any activity that asks no more of the eco-system upon which it depends than what that activity's fair share of that eco-system can provide on an ongoing basis can be said to be sustainable. But since all human activities ultimately depend upon the one eco-system known as Planet Earth, we need the sum total of all human activities to ask no more than what the planet can provide, meaning a consumption rate of 1.0 or less and an overshoot of December 31st or later, which would, of course, be no overshoot at all.

So, perhaps we should be asking ourselves over these next four month of borrowed time is, what can we do to reduce our debt and make next year a more sustainable one.