The Berlin Polarization Monitor: A Panel Study of Partisan and Issue-Based Polarization in Germany (2025–2027)

Affective polarization -- across party and issue divides -- constitutes a key challenge for contemporary democracies. However, systematic data to study longitudinal dynamics of issue-based affective polarization, in addition to partisan divides, remains scarce, especially in the context of multi-party systems. To address this, we introduce the Berlin Polarization Monitor, a 15-wave panel survey running from 2025 to 2027 on partisan and issue-based polarization, emotions, political behavior, personality traits, and well-being in Germany. It covers a wide range of issue-related polarization, including asylum policy, climate change, cordon sanitaire, as well as multiple dimensions of economic and social policy. Feeling thermometers for partisan- and issue-based groups are complemented by precise measures of discrete emotions. This enables the validation of thermometer scores, as well as the study of the emotional foundations of political conflicts and a wide range of related outcomes, including collective action, trust, and coping strategies. Its longitudinal design allows examining within-person changes in polarization and the effects of politically salient events such as elections and crises. The study period includes the 2025 federal election and several regional elections. Overall, the Berlin Polarization Monitor provides a innovative research infrastructure borne out of interdisciplinary collaboration, with particular relevance for political science, psychology, and sociology.