In Shelley’s vision, Frankenstein was the modern Prometheus. The hip, up to date, learned, vital god who chose to create human life and paid the dire consequences. To Shelley, gods create and for humans to do that is bad. Bad for others but especially bad for one’s creator.
Solar geoengineering rests on a simple idea that it is technically possible to make the Earth a little more reflective so that it absorbs a little less sunlight, which would partly counteract some of the risks that come from accumulating carbon dioxide in the atmosphere. When I say technically possible, it appears that at least doing this in a crude way is actually easy, in the sense that it could be done with commercial off-the-shelf technologies now, and it could be done at a cost that is really trivial, sort of a part in a thousand or a part in ten thousand of global GDP.