Affective Inertia in Singapore’s AI Sustainability Discourse: Structural Topic Modeling and Emotion Dynamics on Reddit

Singapore’s AI sustainability discourse has intensified around data centre energy demand and ESG finance, yet how public attention and affect co-evolve in response to policy events remains poorly understood. This study analyses 3305 Singapore-related Reddit documents (709 original posts, 2596 comments) from 2022 to 2025 using Structural Topic Modelling (K = 15) and transformer-based emotion classification. Topic prevalence is modelled as a function of year; emotion classification is restricted to original posts as discourse-initiating units. Three focal events structure the analysis: ChatGPT-3.5’s launch (November 2022), Singapore’s National AI Strategy 2.0 (December 2023), and intensified ESG attention (March 2024). Results reveal pronounced event-linked topical restructuring, most notably a 345% surge in Energy Markets discourse following ChatGPT-3.5, alongside compositional shifts confirmed by ILR-transformed Welch t -tests and Euclidean distance analysis. However, the affective register of original posts remains stable and predominantly neutral throughout, with intermittent fear (mean classifier confidence 71.3%) and no evidence of sustained directional change in emotion intensities. Latent dimensional analysis identifies three affective structures, namely Pragmatic Neutrality, Evaluative Engagement, and Affective Valence, with AI energy topics clustering in the pragmatic-curiosity region. These findings suggest that Singapore’s technocratic governance culture and affective saturation from chronic environmental exposure produce a discourse in which topical reconfiguration unfolds without corresponding emotional mobilisation.