Policy institutional architectures, experimental politics and governing post-carbon green transitions

Cities and states increasingly acknowledge and address major challenges. In many cases, these challenges concern environmental issues such as climate change, urban nature and biodiversity, water and air pollution that interweave with issues of social inequality, community cohesion, mobility and disintegration, forming a complexity to be managed by policy institutions at multiple levels and of diverse capacities. These challenges, in particular climate change, together with e.g. digital technologies, fluctuating political systems, rising mobility, and urbanisation, currently transform cities and lead to changing forms of governance at and between multiple levels of governing. Such developments occur to an extend where new forms of politics and governance are emerging and explored as response to the complexity of challenges and the changing contexts for public governance/governing. Studying governance for sustainability reveals a variety of innovative approaches to governing which covers ULLs, adaptive governance, innovative policies, new forms of participation and institutional adaption to include new types of policy actors, forms of knowledge, norms and policy practices. Policy institutions in these endeavours seek solid ways to cross fragmented and sectorized policy making, align governing rationalities, while also managing the complexity of public policy issues. This involves promotion learning/innovative capacity of policy institutions, metagovernance and to formally or informally commit societal actors through engagement, extent the embeddedness of sustainability and transformational agendas in the business community and civil society. Jointly, this trend in governance aims to manage increasing complex and interlinked policy issues while also stimulating changes, and has been termed experimental politics and sustainability/post-carbon transitions. In this paper, we investigate these forms of experimental politics for a sustainable post-carbon future in the context of transforming societies and governance systems at multiple levels of governance. We examine the question of how experimental politics affect policy institutions and types and logics of governing in attempts to manage the interlocked, knowledge intensive and multi-actor policy problems which major challenges present. Furthermore, we explore which new forms of governing emerge and the dynamic policy learning that takes place in particular policy institutions to manage highly complex and cross-sectoral policy problems such as climate change, social inequity and biodiversity. The study examines these issues in three case studies of European cities that aim to stimulate sustainability transformations through integration of nature-based solutions in public policies, strategies and measures and in co-creation processes that involve citizens, stakeholders and businesses. Findings suggest that the specific policy institutional systems and cultures stimulate or hinder cross-sector capacities for innovative policy learning and adaptive governance to manage complex and dynamic policy problems.