Sustainable travel with carbon offsetting – a study of revealed and stated preferences

Abstract

A promising approach to decarbonizing tourism is to empower tourists to support climate mitigation efforts through the purchase of voluntary carbon offset products. Developing travel-related offsets requires a comprehensive understanding of both the voluntary offset market and tourists’ preferences and decision-making behaviors. First, this thesis conceptualizes Travel Carbon Offsets (TCO) by examining the history, mechanism, and characteristics of voluntary offsets. Based on this foundation, a discrete choice experiment (DCE) was conducted to collect individuals’ stated preferences (SPs) for TCO, exploring tourists’ willingness to choose TCO and the factors influencing their preferences. Results indicate that tourists are generally willing to engage with TCO, with preferences shaped by offset- and travel-related attributes such as project type, cost, green trust, and socio-demographics. While SP data provide insights into attribute trade-offs and preferences for novel products, a key limitation is the potential gap between stated intentions and real-world behavior (Louviere et al., 2000). To mitigate these concerns, the second study of this thesis, following the data enrichment paradigm, examines discrepancies and consistencies within and across SP and revealed preference (RP). By developing and comparing combined models, this study identifies differences in scale, individual- and alternative-specific heterogeneities, and state dependence. It also suggests that a partial data enrichment strategy—where preference homogeneity holds only for a subset of attributes—can more effectively harmonize SP and RP than a full enrichment approach. SP and RP analyses, grounded in the random utility theory (McFadden, 1974), are classified as predictive choice models, which focus on quantifying and forecasting choices rather than examining the underlying psychological processes that explain how and why people make particular choices. To address this gap, the third study conducts qualitative interviews with tourists, both with and without prior offsetting experience. Through thematic analysis, four interrelated themes emerge—awareness and knowledge, motivations and attitudes, project attribute preferences, and trust and credibility. These themes are explored through the integration of psychological, process-oriented perspectives with the economic, structure-oriented framework, providing deeper insights into the process behind utility maximization in carbon offset choices. This triangulated thesis, comprising three complementary studies, makes three key contributions. First, it broadens the scholarly discourse on tourism and carbon offsetting by introducing the possibility of industrywide TCO, moving beyond the predominant focus on carbon offsets for flights. Second, this thesis employs a data enrichment approach to integrate and compare SP and RP data, deepening the interpretation of SP results and offering an updated approach for future research on tourism and carbon offsets. Lastly, by integrating behavioral and predictive approaches, this thesis bridges the gap between these traditionally distinct paradigms, enriching choice research within both the psychological and economic domains. The findings contribute valuable knowledge to academic and practical domains by clarifying tourists’ real preferences and decision-making processes regarding carbon offsetting, and bringing them closer to accurately valuing carbon offsetting behavior, which can guide the development of decarbonization products in tourism.