IPCC Expert Meeting on Geoengineering

Annex 5: Breakout Group Reports
Breakout Group I.3: Carbon Dioxide Removal Options and Methods
Chair: Peter Haugan
Rapporteur: Johannes Lehmann
The summary that follows, written by the Chair and Rapporteur, characterizes the main points of the BOG I.3 discussion. It
may not reflect the personal views of the BOG’s Chair and Rapporteur. The summary is intended for consideration by <strong>IPCC</strong>
authors of the Fifth Assessment Report (AR5), but is neither endorsed nor approved by the <strong>IPCC</strong> or its Working Groups.
Participants in the BOG considered a series of questions related to geoengineering research, developed by the meeting’s
Scientific Steering Group.
Questions suggested for discussion:
What are the most important Carbon Dioxide Removal approaches that <strong>IPCC</strong> authors might want to consider in
the AR5?
What are the most important aspects of these approaches to evaluate (e.g., physical impacts, time scales, system
boundaries, spatial scales, direct/private costs)?
Can the most important aspects of these issues be supported by reference to the peer-reviewed literature, ideally
drawing from multiple lines of independent evidence? What is the available evidence and what are relevant
references?
Introduction
This BOG’s discussion concentrated on identifying major Carbon Dioxide Removal (CDR) approaches that might be
considered in the AR5, evaluating issues relevant to development and implementation of the approaches, and considering
the peer-reviewed literature on development aspects. In addition, the group spent time discussing the terminology of
geoengineering.
What are the most important Carbon Dioxide Removal approaches that <strong>IPCC</strong> authors might want to
consider in the AR5?
The group wrestled with whether the terms “geoengineering” and even “Carbon Dioxide Removal” are appropriate
organizing principles for associated technologies within the context of the <strong>IPCC</strong> or national debates. While the choice of
terminology may at this juncture be unavoidable for multiple reasons (historical development, risk of “white-washing”,
etc.), the organizing principle may benefit from rethinking.
The unifying characteristic of currently grouped CDR approaches is creation of a storage issue. This can be used as a highlevel
organizing principle to distinguish with Solar Radiation Management (SRM). Other organizing principles worth
considering include the following:
<strong>IPCC</strong> <strong>Expert</strong> <strong>Meeting</strong> on Geoengineering - 74