Miserable Earth Overshoot Day

[purpletigron]

Apparently, this Saturday 21 August is Earth Overshoot Day 2010 ... the day when the human population of the planet collectively goes into 'global debt' with the rate at which we've used natural resources during the year: http://www. ( Read more... )

Comments

[drplokta]

I suggest simply ignoring this report, whose methodology is flawed beyond belief. I shall quote one sentence to illustrate: "We chose for our current Ecological Footprint accounts to include nuclear power as if it were fossil fuel."

[purpletigron]

Speaking as an astrophysicist, that doesn't look like show-stopper from an orders-of-magnitude perspective. I'm not up to speed on current best calculations, but I am aware of one life-cycle analysis of near-current nuclear technology which estimated the greenhouse gas emissions to be roughly 50% of near-current natural gas technology, expressed per unit electrical energy delivered, for example.

More fundamentally, do you have an analysis to show that, beyond reasonable doubt, humanity is living within the carrying capacity of the Earth?

I think the key questions revolve around the balance of probabilities on the available reliable evidence, and how, guided by the precautionary principle, we should respond.

[drplokta]

The solar energy flux at the earths surface is around 100 petawatts. Current human usage is around 15 terawatts, so there's room to multiply energy consumption more than a thousandfold.

Given sufficient energy, and we've just established that there is sufficient energy, you can feed a person well on 1/10 of a hectare. The report you quote indicates 11.2 billion hectares of bioproductive surface, so we need less than 10% of that to feed 10 billion people (and less again, because non-bioproductive land can also be used, given sufficient energy).

The rest is engineering -- but the human race is notably good at engineering, and notably bad at mass changes in lifestyles, so let's play to our strengths.

[purpletigron]

Indeed, the theoretically available solar energy, and the theoretical yield of food per hectare, are both encouraging numbers.

I agree that mass changes of lifestyle are hard to precisely engineer. But they have _emerged_ a number of times during human history.

I agree that humans are good at engineering projects, but I'd argue that we're notably bad at spreading the benefits of our engineering innovations evenly amongst global inhabitants.

Which practical examples of humans eating well from 0.1 hectare do you consider to be most relevant? How do you propose to replicate these globally?

[beamjockey]

How big are the error bars on the "overshoot" date? A week? A month?

[tobyaw]

Is there a problem with “liquidating planetary capital”? If we, as a planet, wish to maintain and improve the quality of our lives, then isn’t it good to use the resources available to us?

[sci]

Well before we make any changes, we should really make a backup. So I propose either some spaceborn wildlife preserves, or using electrostatic confinement to compress the asteroid belt into a mini earth (less active maintenance afterall).

But in seriousness, the ways out of this situation are too involved for a little comment box. But I will say that many plans are flawed, aiming to find an unchanging status for the planet which is incompatible with the nature of life.