Strategic metals, rare earths, green transition, and tanker markets: Dynamic connectedness and strategic decision-making

The global energy transition is reshaping not only energy production systems but also the financial and logistical structures that support them. Maritime energy transportation markets and strategic metal markets represent two critical components of this transformation, yet their joint dynamics remain insufficiently explored. This study examines how energy transportation markets, particularly tanker shipping, interact with strategic metals and clean energy financial indices, and how these relationships evolve during periods of structural change and systemic shocks. Using high-frequency daily data from 2015 to 2025, the study applies the Generalized R 2 Connectedness (GR 2 DC) framework to analyze time-varying information flows among the Baltic Dirty Tanker Index (BDTI), the Baltic Clean Tanker Index (BCTI), selected strategic metals, namely lithium, nickel, cobalt, and clean energy exchange-traded funds. The findings show that since 2020 the BCTI has become increasingly synchronized with clean energy and strategic metal markets, reflecting a closer alignment with green investment dynamics. In contrast, the BDTI displays more reactive and lagged spillovers, particularly during periods of geopolitical stress such as the Russia–Ukraine conflict. Overall, tanker freight indices predominantly act as net receivers of volatility rather than persistent transmitters, though the BCTI exhibits episodic transmitter characteristics during crisis periods. The findings indicate that tanker freight indices function as financial signals of structural change in the energy system, rather than merely reflecting physical transport conditions. From a policy perspective, the findings suggest that maritime decarbonization strategies should be evaluated alongside considerations of resource security and supply-chain resilience, supporting a more integrated approach to energy and transport policy design. • Analyzes dynamic connectedness between tanker markets and strategic metals. • Uses the Generalized R 2 Connectedness (GR 2 DC) framework with high-frequency data. • Reveals asymmetric and lag-sensitive spillovers under crisis conditions. • Identifies BCTI's alignment with clean energy and BDTI's exposure to metal shocks. • Offers policy insights on resource security and maritime decarbonization.