Geoengineering is a staple of online conspiracy theories. Just Google “chemtrails”. But apparently it’s becoming reputable as a way to save the planet. The only good news here is that any such attempt is likely to fail if attempted. But the bad news is it might work, and we might not be able to control the outcome. We just don’t know enough about climate to go throwing it off kilter. What if we triggered another ice age and killed 90% of humanity? Ooops would not suffice.
For those who were not frightened by a Saul Bellow novel in their youth, the reference in our headline is to Henderson the Rain King and specifically the episode in which would-be do-gooder Eugene Henderson comes to an African village whose drinking water cistern is infested by frogs and devises a plan to blow them up. Which works, sort of. His improvised explosive detonates, filling the cistern with revolting frog parts before its blast-damaged wall collapses, emptying the cistern and leaving the villagers without water. The moral is don’t assume the power of a god unless you also have the wisdom of one.
We don’t. Including on the technical aspects of climate, of causation and even of measurement, let alone the cosmic question if we really could set the global thermometer to any level we chose, what level we would choose. It is far from obvious that the climate of 1970, or 1950, is the perfect temperature Gaia has been trying to reach all along, rather than say that of 1200 or 49 BC, both of which being “natural” cannot be rejected as tainted by human conduct.
We hope we have by now induced at least some readers to flinch at every headline containing the phrase “scientists say” as if there were a scientific consensus on most topics and journalists would know what it was if there were. Like “Asteroid Dust Could Help Cool the Climate, Scientists Say”. The likelihood that an attempt to cool the Earth would have any effect at all is, fortunately, small, since we don’t know by how much it would cool it, what runaway process we might trigger especially as the Holocene appears to be close to the normal end point for recent interglacials, and what sorts of complex feedback effects might be triggered.
Surely the concept of lassoing an asteroid, parking it at a gravity-neutral “Lagrange point” between the Earth and the sun and letting it shower us with dust falls into the “What could possibly go wrong category?” Especially as even the proponents admit it could fall on us and wipe out a city.
At any event, it’s odd to say oh no, arrogant humans have disrupted the biosphere and then rub your hands and announce plans to do it again. First, do no harm. Second, go away.