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156 Environmental Change and Sustainability

Climate change or "global warming" is a major issue within the debate about the sustaina‐ bility of social and natural systems. In this context it has become the prime example for poli‐ cy problems that are characterized by long time horizons, large uncertainty and high ambiguity [1]. In such a policy context, problem definitions get vague and unstable, prefer‐ ences become unclear, and the potential of social conflict is high [2]. Under these circum‐ stances, policy making heavily relies on public discourse in which issues and interest conflicts are collectively debated and shared "definitions of the situation" are constructed. For this reason, the issue of climate change has attracted high attention among policy re‐ searchers interested in discourse analysis since the early 1990s.

While many empirical studies focus on the rise and decline of discourse activities, some crit‐ ics have questioned the relevance of climate change discourses at all. For instance, even scholars of cultural studies such as [3] call for a *"return from the world of discourses and systems back to the actions and strategies with which social beings try to manage their existence"*. Such a perspective implies that policy problems are seen as objectively given and self-evident, without any need to be collectively defined and represented. In an epistemological perspec‐ tive, this is a naïve version of realism [4]. According to our perspective, however, public dis‐ course is an essential part of policy-making, besides the interests, preferences and strategies of all involved actors and the institutional constraints in which policies are decided and im‐ plemented. Policy-controversies and debates are not just "surface phenomena" of political processes but are rather an integral part of power structures and exchange relations in poli‐ cy-making. The analysis of public debates and policy discourses – in a qualitative or quanti‐ tative manner – can therefore be seen as an important component of policy analysis [5].

© 2013 Schneider and Ollmann; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 Schneider and Ollmann; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

In this paper we will apply a specific form of quantitative discourse analysis to the de‐ bate on global warming and related policy decisions. Since qualitative discourse analysis runs short in terms of transparency, comparability and replicability, we use various methods of quantitative structural analysis to specify the role of actors and their interre‐ lations within the policy discourses on climate change [6]. Recent methodological devel‐ opments, namely the combination of category-based, computer-assisted, qualitative content analysis and social network analysis [7-9] provide new possibilities to analyze discourse coalitions, actor constellations, conflict structures, and their dynamics at the level of discourses and policy debates.

The specific goal of our paper is to trace and interpret the evolution of German public discourse on climate change in terms of punctuated equilibrium theory (PE theory), which is a distinctive version of evolution theory in the natural and social sciences. It re‐ jects gradualist assumptions and emphasizes discontinuities in processes at all levels which have been triggered by great and singular events [10]. When applied to social de‐ velopments, PE theory explains policy change as a result of major shifts in the public perception of a policy issue, which in turn is triggered by focal, and often "external" events [11]. These processes are intermediated by negative and positive feedback mecha‐ nisms that accelerate or slow down developments.

Our study will assess core propositions of PE theory with respect to the impact of the finan‐ cial crisis on the German climate discourse between 2007 and 2010. Germany has been wide‐ ly acknowledged to be a front-runner in climate policy on the European and global level. A commonly accepted explanation is that intense public participation and strong public con‐ sensus based on "ecological modernization" have contributed to this success. Even though this consensus has dominated the German discourse for over two decades, some scholars [12, 13] have issued concerns that it might prove to be unstable. Since its peak in 2007, public attention to the issue of climate change has been declining. Our data show that this downswing seems to have been strongly amplified due to the financial and economic crisis in 2008 and 2009. In the context of this massive downturn, actors changed their discursive be‐ havior, impacting actor positions and frame constellations.

Our paper proceeds in three steps. In the next section we will give a short outline of various theoretical perspectives in the analysis of policy discourse, emphasizing punctuated equili‐ brium theory. Our third section proposes a formal and quantitative approach to structural analysis of discourse configurations that are linked to actor networks. In the fourth section we will apply this approach to policy discourse in the domain of global warming in Germa‐ ny under the influence of the recent economic crisis. In the conclusions we summarize our findings and raise some question for further analysis.
