The Convention on Biological Diversity just released a report [PDF] put together by their Liaison Expert group on geo-engineering and biodiversity. The report – to which I have contributed as one of several lead authors – brings together peer-reviewed literature on expected impacts of a suite of geoengineering technologies, on biodiversity and ecosystem services. The last chapter also elaborates social, economical and ethical dimensions as they relate to the technologies’ impacts on biodiversity. Key messages include:

10. There is no single geoengineering approach that currently meets all three basic criteria for effectiveness, safety and affordability.  Different techniques are at different stages of development, mostly theoretical, and many are of doubtful effectiveness. Few, if any, of the approaches proposed above can be considered well-researched; for most, the practicalities of their implementation have yet to be investigated, and mechanisms for their governance are potentially problematic.  Early indications are that several of the techniques, both SRM [Solar Radiation Management, my addition] and CDR [Carbon Dioxide Removal, my addition], are unlikely to be effective at the global scale.

42. Geoengineering raises a number of questions regarding the distribution of resources and  impacts within and among societies and across time. Access to natural resources is needed for some geoengineering techniques. Competition for limited resources can be expected to increase if land-based CDR techniques emerge as a competing activity for land, water and energy use. The distribution of impacts (both positive and negative) of SRM geoengineering is unlikely to be uniform – neither are the impacts of climate change itself. (Section 6.3.4)