Political processes affect the feasibility of climate policy in Integrated Assessment Models

Public backlash may topple climate policies, as unpopular measures with adverse economic effects can lead to electoral losses for green parties. However, Integrated Assessment Models (IAMs) typically focus on cost-effectiveness, ignoring political feasibility. In this study, we couple an election model to the agent-based Dystopian Schumpeter–Keynes (DSK) IAM by introducing a “green” party and a “brown” climate-denying party that never implements climate policy. Voters are swayed by climate concerns, economic impacts, or unrelated issues. We explore political processes in stylised scenarios to assess the feasibility of carbon pricing, a key mitigation tool. We find high carbon taxes lack political feasibility, as interruptions impair effectiveness, harm the economy, and deter green votes. Policy mixes of regulations and subsidies, paired with mild carbon taxes to cover costs, perform better. Our results suggest the IAM community should integrate political feasibility into assessments.