This post, in addition to being quite compelling, reminded me fondly of an early post here at Organic Matter – enough that I thought I’d make a note of it for anyone who didn’t catch it at Worldchanging (you mean to tell me that you don’t read Worldchanging?!?).

While I talked about the ridiculousness of talking about terraforming another planet before bothering to learn how to live sustainably on Earth, Jamais talks about terraforming the Earth itself (although Mars does get honorable mention in the comments):

[...] Even if every human and human artifact disappeared tomorrow, the changes we've made to the water, soil and atmosphere would continue to exist for decades, centuries, even millennia. The question isn't how can we stop changing the planet, the question is how we can do so more wisely, avoiding the changes most harmful to the planetary ecosystem, and applying greater recognition of the long-term effects of our changes.

[...] We're already making big changes, only without any foresight or design; to paraphrase Stewart Brand's 1968 epigram, we are already terraforming Earth, and might as well get good at it.

Each of the ideas that Jamais goes on to discuss has significant drawbacks, due to either environmental uncertainty or economic cost – or both – but the thrust of his argument is twofold:

(1) willful ignorance of our climate problem has created a situation in which significant warming is already built into the climate system, and we have no choice but to adapt to a warmer Earth regardless of the degree to which we abate carbon emissions; and

(2) the most extreme consequences of climate change are potentially so dire that we must be willing to consider measures that might otherwise seem too expensive or risky.

I don’t mean to suggest that hanging a circular mirror over 600 miles in diameter between the Earth and our sun is necessarily cost effective, but I’m always glad to know that people are thinking of innovative ways to deal with complicated problems. It’s clear that emissions reduction is our first defense against a changing climate, but we also know that we’re already guaranteed to face at least another ~0.5°C of warming, so we’d better have the technology to deal with it.