- Model runs simulating space mirrors show that global temperature increases can be offset, but at the cost of suppressed precipitation relative to preindustrial conditions.
- Stratospheric aerosol and marine cloud brightening models both show more muted climate responses, but termination effects are significant when either method is stopped abruptly.
- The world economic effects of SRM are unclear, although they could be negative partially due to altered precipitation patterns.
The report concludes, "the potentially strong climate responses discussed here suggest that climate engineering cannot be seen as a substitute for a policy pathway of mitigating climate change through the reduction of greenhouse gas emissions" (p. 10). Sadly, it bears repeating that no serious proposals to substitute geoengineering for mitigation exist, a fact which the authors of the IMPLICC report are most assuredly aware.