One of the world’s pre-eminent scientific publications, Nature, issued a scathing report card in advance of this week’s Rio+20 summit on sustainable development. The grades for implementation of the three great treaties signed at the first Rio Earth Summit in 1992 were all bad: Climate Change – F; Biological Diversity – F; and Combating Desertification – F. Can humanity still avoid getting itself expelled?

We have known for at least a generation that the world needs a course correction. Instead of powering the world economy with fossil fuels, we need to mobilize much greater use of low-carbon alternatives such as wind, solar and geothermal power. Instead of hunting, fishing, and clearing land without regard for the impact on other species, we need to pace our agricultural production, fishing, and logging in line with the environment’s carrying capacity. Instead of leaving the world’s most vulnerable people without access to family planning, education, and basic health care, we need to end extreme poverty and reduce the soaring fertility rates that persist in the poorest parts of the world.

In short, we need to recognize that with 7 billion people, all interconnected in a high-tech, energy-intensive global economy, our collective capacity to destroy the planet’s life-support systems is unprecedented. Yet the consequences of our individual actions are typically so far removed from our daily awareness that we can go right over the cliff without even knowing it.

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