Cape Town, 27. August 2009 Page 1 Science and ethics of climate scientists Hans von Storch Institute of Coastal Research, GKSS Research Center Geesthacht clisap-Center of Excellence, Klimacampus, University of Hamburg Germany

Cape Town, 27. August 2009 Page 2 Who is this? Hans von Storch (born 1949) Director of Institute for Coastal Research, GKSS Research Center, near Hamburg, Professor at the Meteorological Institute of Hamburg University Works also with social and cultural scientists. Raised in Germany, thus probably strongly influenced by German culture.

Cape Town, 27. August 2009 Page 3 Science and scientists

Cape Town, 27. August 2009 Page 4 What is the role of science in society? Think-tank for providing solutions to social, technological and political problems. As such subordinated to current political agenda and societal value-setting, or Cultural achievement of rationally understanding complex phenomena, independent of “Zeitgeist”.

Cape Town, 27. August 2009 Page 5 What is the role of science in society? In both cases science is a meaningful social institutions which provides a service to society. It can provide this service sustainably or non-sustainably, as all social practices.

Cape Town, 27. August 2009 Page 6 Sustainability in science means … … a conduct which can be extended into the future without consuming its basis for utility, which consists of trustworthiness competence independence - Consuming its basis for utility means takes place by disregarding its limits of competence, and by honoring special (hidden) interests (ideological, political, economic) by overconfidence and downplaying of uncertainties.

Cape Town, 27. August 2009 Page 7 A typology of scientists (interacting with the public): the pure scientists the arbiter the advocate the honest broker

Cape Town, 27. August 2009 Page 8 Climate Science

Cape Town, 27. August 2009 Page 9 Constructions, post-normal Climate change is a „constructed“ issue. People do not really experience „man made climate change“. One construction is scientific, i.e. an „objective“ analysis of observations and interpretation by theories. The other construction is cultural, in particular maintained and transformed by the public media. Climate science is in a “post-normal phase”, i.e., no longer driven mostly by curiosity but driven by its argumentative utility in a political struggle, while at the same time ridden by substantial uncertainties.

Cape Town, 27. August 2009 Page 10 Lund and Stockholm Two different construction of „climate change“ – scientific and cultural – which is more powerful? Cultural: „Klimakatastrophe“ Scientific: man-made change is real, can be mitigated to some extent but not completely avoided Storms Temperature

Cape Town, 27. August 2009 Page 11 The scientific construction Climate is changing on time scales of decades and centuries. Presently climate is changing mainly because of elevated concentrations of greenhouse gases in the atmosphere. This change is best detectable in temperature and related quantities, and will become visible during this century also in other variables, in particular related to the water cycle. Climate change has an impact on social life and ecosystem functioning.

Cape Town, 27. August 2009 Page 12 Possible Reponses to Anthropogenic Climate Change In the interacting environment-and-society system, we have two classes of options for response: trying to avoid man-made changes („mitigation“) – this has different dimensions, namely avoiding elevated levels of GHG concentrations by reduced emissions; by intensified sinks; by geo- engineering the global albedo, or regional and local conditions. adapting to man-made changes („adaptations“) of climate. In principle, limiting the cause of anthropogenic climate change (i.e., reduction of emissions) is preferable over adaptation, but complete mitigation seems impossible so that the best strategy is to mitigate as much as affordable and to minimize negative consequences by adaptation.

Cape Town, 27. August 2009 Page 13 A framework of how to think about response strategies (Hasselmann, 1990)

Cape Town, 27. August 2009 Page 14 Is scientific knowledge driving the policy process?

Cape Town, 27. August 2009 Page 15 The science-policy/public interaction is not an issue of „knowledge speaks to power“. The problem is not that the public is stupid or uneducated. The problem is that the scientific knowledge is confronted on the „explanation marked“ with other forms of knowledge (pre-scientific, outdated; traditional, morphed by different interests). Scientific knowledge does not necessarily “win” this competition. The social process „science“ is influenced by these other knowledge forms. Science can not be objective but should nevertheless strive to be so. Knowledge market

Cape Town, 27. August 2009 Page 16 Final comment: science, policy and responsibility (Geophysical, ecological) Science should not formulate policy, but prepare the factual basis for decision makers, who consider apart of geophysical and ecological facts also other, in particular normative arguments. Climate change is real and mostly caused by human emissions. Society wants to avoid such a change; thus, reductions of emissions are needed („mitigation“). Any conceivable mitigation policy will not lead to an ending or even reversal of global warming; thus the need for adaptation emerges.

Cape Town, 27. August 2009 Page 17 Epilog: The service of science The debate about global warming has rightly become a political debate, which unfortunately spills over to science – where scientists act as “stealth advocates” for value-based agendas. In the course of this process, the authority of science is eroding, as it becomes difficult to distinguish between scientific analysis from science and advice from NGOs or other value-driven social actors. In this model, science adopts the role of auxiliary troops for broader social movements. To maintain the service provided by science to society – namely to provide “cold” knowledge which may help to sort out some aspects in an otherwise passionate and value-driven decision process – scientists should limit themselves to assessment of robust scientific knowledge and should avoid normative statements beyond their expertise. (They may do that if they act as citizens, of course.) Politicization damages the social institution “science”.