Emergency geoengineering & the virtues of Earth stewardship

Geoengineering is increasingly considered a plausible and possibly justified response to global climate change. At least one proposed form of geoengineering, solar radiation management (SRM), would attempt to intentionally manipulate systems at the planetary scale for human ends and, as such, counts as an effort toward planetary management. Thus, arguments that SRM could be morally permissible are committed to the possibility that at least some form of planetary management is not morally impermissible. By contrast, many philosophical views developed as an environmental ethic advance a principle of nonintervention, especially concerning genomic and atmospheric systems. Those who favor a virtue-theoretic approach often object to aspirations of planetary management as hubristic. In this paper, I argue human beings have a moral obligation to serve as planetary managers and it is possible to occupy this role without hubris. Responsible planetary management is a moral good and constitutes virtuous Earth stewardship. However, I argue if virtuous planetary management is possible, then SRM geoengineering cannot be consistent with satisfying that role well; no virtuous planetary managers would develop or deploy technologies for SRM geoengineering. It is reasonable to believe the possibility of deploying SRM as a “lesser evil” in a hypothetical, emergency choice situation will present future generations with a genuine moral dilemma and, consequently, presents virtuous agents today with a moral emergency. If we have an obligation to manage the planet, then virtuous exercise of the associated practices could never include deploying geoengineering by means of solar radiation management, including stratospheric aerosol injection.