Integrated Assessment Models

These notes provide a summary of the discussion and conclusions of a meeting on Integrated Assessment Models (IAMs). The meeting, convened by Professor John Schellnhuber, was an opportunity to provide early input into the newly emerging Integrated Assessment research theme of the Tyndall Centre for Climate Change Research. Eight representatives from the Tyndall Centre, four from ICIS (International Centre for Integrative Studies), and about 15 from the PIK (Potsdam Institute for Climate Impact Research) participated in the meeting (Appendices 1 and 2).

The main aim was to bring together three established and emergent players in the European IAM theatre for intensive brainstorming on the way forward. Four major tasks need to be tackled in order to make substantial progress during the next three to five years, namely:
(i) generating concepts for the third generation of IAMs;
(ii) identifying and realizing novel applications with existing and/or forthcoming models;
(iii) clarifying the relationship between IAMs and Regional/Sectoral Simulators; and
(iv) determining the division of construction and operation labour within the national, European and global IAM communities, respectively.

Most of the available time was actually spent on item (i), but the other items were implicitly taken into account - especially through the breakout groups (Appendices 3-5). The question of cooperation (item iv) received the attention it deserves as it seems rather impossible today to build a state-of-the-art IAM from scratch as a stand-alone institution - the splendid IMAGE story will not be repeated. So meta-modelling and distributive schemes are likely to dominate the medium-term future, at least.

The workshop was kicked off by brief overviews of pertinent activities at the three research institutes involved. The following brainstorming phase was initiated by the convenor's presentation of three different options for the design of third generation IAMs. These are not mutually exclusive, but each option has rather different implications for organisational structure and implementation. Their philosophies are also rather different (Appendix 6). The general discussion identified three crucial issues to be explored in breakout groups:

Group 1:IAM - Stakeholder interaction
Group 2:What new elements are needed for third generation IAMs?
Group 3:The architecture of a new (third) generation of IAMs.

Summaries of the deliberations of each group are provided in Appendices 3 to 5.