Bumsuk Seo (Germany) 1; Calum Brown (Germany) 1; Mark Rounsevell (Germany) 1
1 - Karlsruhe Institute of Technology
Modelling studies of the role of policy in climate change adaptation invariably treat policy actions as exogenous drivers of change. There is no recognition of the interactions between policy makers and the actors affected by their policy interventions, nor of the capacity of policy makers to monitor the changing landscape, and learn through these experiences leading to modified policy choices. Here we present an agent-based model (ABM) of public policy institutions that is formally coupled with an ABM of land users. Institutional agents are able to monitor and hence observe land use change, and in response to their ascribed goals implement a number of different policy actions.
The model consists of institutional agents at two hierarchical levels: global and regional institutions. The higher-level institution (‘global institution’) influences lower-level institutions (‘regional institution’) by setting policy goals, direct interventions, and providing a budget for policy implementation. The regional institutions are characterised by their policy sector (e.g. agriculture, forestry, nature conservation) and are able to enact a number of actions (policy instruments) that directly affect land user behaviour and choices. These actions include policy based on legal and regulatory instruments (e.g. protected areas), rights and customary norms (e.g. common land rights), economic and financial instruments (e.g. subsidies, taxes), and social and cultural instruments (e.g. education, knowledge exchange). This architecture broadly follows the hierarchical governance modes observed within nation states. However, we are also able to modify the governance mode by placing more or less emphasis on the global or regional institutions and their actions. This includes governance that is decentralised, based on public-private partnerships, or driven primarily by the private sector. The efficiency and cross-sectoral and transboundary impact of the policy actions are quantified in simulations with the ABM.
We demonstrate how the model can be used to undertake experiments in public policy decision making, with an emphasis on the implications for adaptation planning under high-end climate change. We find that subsidy levels have the greatest impact on the magnitude of land use change and the supply of ecosystem services in adapting to climate change. Although a number of other policy instruments, combined in policy mixes, can also contribute to climate change adaptation. The approach also allows experiments on the effectiveness of different governance modes and policy instruments under various environmental change conditions, including experiments that seek to identify robust policy options across a range of future conditions.