A truly awful idea

As if to confirm the mentally unbalanced nature of the "global warming" craze, along comes the recent movement pushing for geoengineering, large-scale modification of the Earth's atmosphere and oceans, all to prevent a pseudo-crisis.

It's hard to decide what's the worst thing about this movement. Is it the hubris of would-be geoengineers in the face of how much we don't know about the Earth's aerohydrosphere? Is it their apparent failure to have learned anything from the experience of weather forecasters in the last 40 years in wrestling with chaos and the long-term unpredictable nature of the weather?

Certainly, the ideas being proposed range from fringe to completely daft. The usual goal, modifying the flow of light into and heat out of the Earth's atmosphere, is not the problem. The atmosphere's heat flow is not too complicated, considered in a general way, although its detailed evolution is impossible to predict. The real problem is the unknown effects that geoengineering schemes would have on the chemistry of the atmosphere and oceans. This chemistry is far more complex and unfathomable than the heat flow.

At this point, the only geoengineering proposals that should even be entertained are either space-based experiments, with self-contained consequences, or augment what's already mitigating carbon dioxide levels: planting trees, or perhaps small experiments with enhancing oceanic absorption of CO2.

Even restricting ourselves to already-known mechanisms involves some risks. To the argument that we can stop geoengineering if it begins to go amiss, consider entropy, irreversibility (the Second Law), and the large qualitative changes the Earth's climate occasionally undergoes (like the Ice Ages). It's like starting to roll down a hill, with no way of getting back to your starting point. Bifurcation happens :)

Geoengineering - on the scales being debated now - is crackpot lunacy.