Scientists and policymakers are meeting this week to discuss whether geoengineering to fight climate change can be safe in the future, but make no mistake about it: We’re already geoengineering Earth on a massive scale.From diverting a third of Earth’s available fresh water to planting and grazing two-fifths of its land surface, humankind has fiddled with the knobs of the Holocene, that 10,000-year period of climate stability that birthed civilization.
The point that humans are altering geophysical processes on a planetary scale is almost inarguable. But while this alteration is an aggregate effect of human engineering, it is not in any sense geoengineering. Geoengineering is the intentional alteration of geophysical processes on a planetary scale, while anthropogenic environmental change as it exists now occurs without such intent (either through ignorance or indifference).
Mr. Keim probably had no hidden agenda himself, but the attempt to blur a distinction of intent into a difference of degree is a common transhumanist move, and a seductively fallacious one. In the case of climate change, it can lead to advocacy for what amounts to fighting fire with fire. As I've argued before, the lesson we ought to learn from global warming is that humans can easily alter complex systems not of their own cohesive design but cannot easily predict or control them.
Just like a project to remake man, a project to remake the planet will have to be so advanced from today's technology as to overcome what is at least now the truth of this lesson — but it will not do so by treating the project as essentially more of the same of what humankind has already done to the planet.