Crisis and cooperation: how natural disasters drive municipalities to join Transnational Municipal Networks

Cities account for a dominant share of global CO2 emissions, making their engagement in climate governance crucial for addressing environmental challenges. This study investigates whether experiences with environmental disasters influence Brazilian municipalities’ decision to join Transnational Municipal Networks (TMNs). Using a heterogeneity-robust Differencesin-Differences framework on a dataset of Brazilian municipalities from 2016 to 2023, we find that experiencing natural disasters leads to increased TMN participation in a delayed manner, consistent with our hypothesized institutional learning mechanism. The analysis also reveals that medium-sized municipalities show the strongest positive response to disaster experiences, while large municipalities exhibit a surprisingly negative relationship between disaster density level and TMN participation.