Three studies on sustainable shipping management : ballast water impacts, market volatility, and seafarers’ rights

Abstract

Sustainable shipping management is vital for achieving the United Nations’ 2030 Agenda for Sustainable Development, addressing environmental (SDG 14), economic (SDG 8), and social (SDG 16) objectives. However, the evolving nature of international trade presents new challenges for maintaining the triple bottom line in the shipping industry. This thesis comprises three empirical studies that investigate the forecasting issues in ballast water, the causal inference issues in market volatility, and the policy evaluation issues in seafarers’ rights. Study 1 develops a generic approach to estimate ballast water discharge volumes and assess associated non-indigenous species invasion risks, employing the LASSO technique in machine learning and a three-stage biological risk spread probability model. Drawing on common port statistics and biogeographical and environmental parameters of Chinese ports, this study forecasts ballast water discharges from bulkers and tankers in China during 2017–2020 and the associated invasion risks in 2017. The study reveals that ports in the Yangtze River Delta and the Bohai Rim receive the most ballast water, tankers have greater discharge potential than bulkers at a per-unit cargo throughput capacity, and Chinese ports face a high probability of alien species introduction exceeding 0.9. This study provides a feasible decision-making tool to help developing countries without ballast water records, such as China, implement the Ballast Water Management Convention during its initial experience-building phase. Study 2 disentangles the relationship between internal spillovers across shipping spot freight markets and external uncertainties. Utilising VAR-based methods, Diebold–Yilmaz spillover indices are constructed for container, dry bulk, dirty, and clean tanker spot markets from 2009 to 2023. The Granger causal and shock effects of Economic Policy Uncertainty (EPU) and Geopolitical Risk (GPR) on these indices are examined, with particular attention to the post-COVID-19 period. The study proves that the pandemic has altered the roles of net spillover transmitters and receivers within the four freight markets, while intensifying the causality and shock impacts of EPU and GPR on spillovers. Additionally, the study indicates that EPU and GPR affect spillovers through distinct mechanisms, with tanker markets acting as mediators that amplify uncertainty shocks. These findings provide policy implications for shipping stakeholders to mitigate uncertainty impacts. Study 3 analyses the effectiveness of the Maritime Labour Convention (MLC) and its financial security amendments in protecting the rights of abandoned seafarers. Using abandonment reports from 2017 to 2023, the study constructs a new dataset and identifies crucial factors affecting repatriation and wage payment rights. With nested logit and fixed effects models, these factors’ effects on the choice probabilities and time efficiency of repatriation and payment are evaluated. The study reveals that Asian abandonment locations and mixed crew nationalities lower repatriation probability, while older ships decrease wage payment likelihood. Port State Control facilitates neither the likelihood nor the timeliness of repatriation. Flag of convenience States and Protection and Indemnity clubs indeed benefit the resolution process of abandonments, but it still takes more than half a year. The findings highlight the MLC’s shortcomings and provide quantitative evidence to support improvements to its relevant provisions.