1. IPCC: needs and options Roles played in the IPCC assessment processes TAR: lead author WG I AR5: lead author in WG II Participation at some expert workshops, and as contribution author. Expert heard at IAC hearing in Montreal, 15 June 2010. Hans von Storch Panel discussion "Status quo and future of the IPCC" at 16.November 2015

2. IPCC main achievements By screening the scientifically legitimate literature, IPCC has determined that - climate is changing (manifestation) - beyond the range of natural variations (detection) - which cannot be explained without referring to elevated greenhouse gases as dominant driver (attribution) Climate made has impacts on the living environment and on society. By steering the emissions of GHGs, the degree of man-made climate change can be limited. The non-avoided man-made climate change needs significant adaptation efforts. The societal conclusions to these insights are a matter of policy.

3. Hans von Storch - 1. Problems - 2. Elements of a solution - 3. Example BACC Real or alleged errors in the IPCC-report Reports contain errors. This is not a surprise given the sheer volume of the reports. AR4: Examples: Himalaya, Low lying part of The Netherlands, endangered food supply in Africa. AR4: All WG 2 (impacts) errors related to exaggerations? Sometimes material provided by interested parties. IPCC has not adopted mechanisms for dealing with such problems. But: No known errors in AR4-WG 1(“physics”) But: No known errors in AR5

4. IPCC impact on the functioning of the scientific community Core groups – quite a few high-profile authors participate repeatedly in the IPCC process in different functions. Formation of “old-boy networks”. Advantage of lead authors – their own papers are elevated to significant contributions. Own scientific agenda tailored to IPCC usage. Work for IPCC (e.g., CMIP) blocks resources from other activities (e.g., at DKRZ). Assertions of IPCC attain status of “truth” in the standard scientific review process. Bias towards anglo-saxon scientific communities. Hans von Storch - 1. Problems - 2. Elements of a solution - 3. Example BACC

5. Elements of improvements A standing committee for running quality management needed. AR(n) report assesses if AR(n-1) contained “errors” or needs re- assessments. AR(n) formulates tasks for AR(n+1) Massive change of assessors from one assessment report to the next. Recognition of post-normal conditions. Have “regional IPCC” assessments as much as possible, using rules of operations given by “global IPCC” (concerning acceptable publications, review process, selection of lead authors …). Have assessment of “global IPCC” for truly non-regional issues, such as sea level, sensitivity, quality of global models. Hans von Storch - 1. Problems - 2. Elements of improvements- 3. Example BACC

6. Insight needed: Climate science is in a postnormal state When facts are uncertain, values in dispute, stakes high and decisions urgent, science is not done for reasons for curiosity but is asked for as support for preconceived value-based agendas. Analysis of two (or many) bodies of knowledge claims, namely (dominantly) scientifically constructed knowledge, and (dominantly) culturally constructed knowledge. Analytical support by cultural sciences needed. Discrimination between scientifically solid core of knowledge vs. politically convenient (contested) knowledge claims. Hans von Storch - 1. Problems - 2. Elements of improvements- 3. Example BACC

7. Regionalization of Assessments: BACC An IPCC-like effort to document the scientifically legitimized knowledge about anthropogenic climate change available for the Baltic Sea catchment. Fist report in 2008, second in 2015. Under the supervision of the (then) GEWEX sub-programme BALTEX. Issues, the IPCC could learn something from BACC: 1. Separation between bookkeeping of knowledge (BACC) and political assessment (HELCOM). 2. Survey among scientists on how well the effort succeeded in tracking the available knowledge. 3. All lead authors are replaced after completion of a report; a new list of chapters and responsible lead authors is selected by a renewed Steering Committee. Hans von Storch - 1. Problems - 2. Elements of a solution - 3. Example BACC

8. Take home IPCC was an indispensable effort. IPCC processes need to be improved. - Mechanism to deal with claims about errors and conflicts of interest. - Consideration that “payment” may take the form of societal or professional recognition, not only in terms of money. - Documentation and highlighting of contested areas and areas of significant lack of scientific analysis. - Mechanisms to prevent formation of networks of lead authors - Factoring into the assessment that scientifically constructed knowledge may be conditioned by culturally constructed (value- based) knowledge claims. Decentralized “regionalization” efforts (aka BACC etc.) where suitable. Panel discussion "Status quo and future of the IPCC" at 16.November 2015