IPCC Expert Meeting on Geoengineering

Annex 5: Breakout Group Reports
Relative Estimated Total Storage Potential
Higher
Lower
Weathering
Direct CO 2
injection
Ocean fertilization
Transboundary
issues
Direct air capture
Afforestation/
reforestation
Little transboundary
issues
Biomass burial
Bioenergy with CCS
Biochar
Conservation agriculture
Forest
No till agriculture
management
Blue carbon Sequestration
in buildings Fertilization
Creation of wetlands of land plants
Carbon absorbing cement
Global Regional Local Local
+ C storage benefit
Project Impact Beyond Climate
Red: Sink creation
Black: Emission reduction
Figure A.5.1: The relative estimated total storage potential for emission reduction and sink creation projects at different
scales.
What are the most important aspects of these approaches to evaluate?
The group’s discussion included the following aspects:
Feasibility (technical, risks)
Effectiveness (time to maximum deployment, maximum rate of CDR (Gt C/yr); maximum integrated storage
potential (Gt))
Side effects (physical, biological, risks, local and global scale)
Efficiency (direct cost, social costs, including side effects)
Legal and social acceptability
Regulation (economic incentives, command and control)
Monitoring and Verification
Ethics (long time scales)
The BOG noted that it is important to distinguish whether research or deployment is to be evaluated.
<strong>IPCC</strong> <strong>Expert</strong> <strong>Meeting</strong> on Geoengineering - 76