Kristie Ebi offered some comments from the perspective of Working Group 2 (WG2) of the Intergovernmental Panel on Climate Change (IPCC). She said that the meeting catalyzed excellent discussions on how the two groups can work together, and she expressed the commitment of WG2 to collaborate with Working Group 3 (WG3) and Working Group 1 (WG1). She noted that many ideas had been raised at the workshop for collaboration and research, which agencies might support. However, she did not hear a proposal for a specific process for working together fast enough to get some of the research put into the IPCC Fifth Assessment. After the workshop report is published, she suggested, the next step could be a paper to propose such a process. She emphasized the need to get the scenario process started quickly, so the results can be used in the IPCC Fifth Assessment.
Timm Zwickel offered some comments from a WG3 perspective. He said that the workshop had been very enlightening. He reminded the participants of a planned meeting on story lines in October 2010 and expressed interest in an agreement on a platform for continuing this process, possibly by phone conferences, and for including the integrated assessment modeling community. Advancing on a common approach to socioeconomic scenarios might be a useful concrete task, and it might be advanced in a paper written by the community or by the leaders of WG2 and WG3.
Anthony Janetos observed that a productive avenue for national scale assessments would be to consider which factors and processes are tightly
or loosely coupled and suggested that Kathy Jacobs could take that issue up with U.S. government agencies. Hugh Pitcher commented that it is important to iterate, including checking ideas with the professionals in the community at least once, before publishing numbers that other people will use for analysis. He noted, for example, that there are now three sets of numbers in use for translating purchasing power parity. Brian O’Neill said that before the fall meeting on story lines, there is a need for a process to get usable input (e.g., quantified drivers) to discuss; the community needs to institutionalize the process. John Weyant mentioned thoughts about continuing the discussions this summer, suggesting that the workshop participants could hold some conference calls between now and then.
Thomas Wilbanks commented on next steps in advancing socioeconomic projections. He intended both to note things he heard and to be a catalyst to others to make suggestions. He asked participants to share ideas about next steps—both what to do and how. Some of the next steps might improve the science for the long term through tool and knowledge development. An example would be developing a library of socioeconomic scenarios, with targeted gap-filling efforts that would promote communication across the communities. He said the participants could also try to strengthen the links between climate change science and socioeconomic projection science (demography, economics, regional planning, political and institutions science, and land use modeling). They could also seek ways to incorporate technical and socioeconomic surprises.
In the near term, Wilbanks suggested the value of developing a small set of socioeconomic pathways—simple narrative story lines that can be placed aside climate change scenarios in order to assess impacts of the projected changes. More could be done to improve understanding of the coupling between climate futures and socioeconomic futures. In the next 2 years, the community could try to develop sets of scenarios to fill the space in a two-dimensional graph with high versus low climate change and high versus low socioeconomic change on its axes. It is important to discuss how the IPCC Fifth Assessment will cope with the likely proliferation of possible story lines. Finally, a shared concern with vulnerability might help the two communities communicate. Wilbanks suggested that the communities can come together most effectively by focusing on tangible issues. He ended by inviting other thoughts from the participants.
Richard Moss concluded the discussion by noting that the community does not have answers to many of the main questions people are raising. He emphasized that conclusions that cannot be supported should not be forced, noting the need to distinguish between research needs and decisions for organizing the next IPCC assessment, which must be taken by the IPCC. He concluded by thanking all participants on behalf of the organizing committee.