This study examines the dynamic interdependence between Clean Energy indices, AI Robotics Index, and selected NFT and DeFi tokens across three major geopolitical crises: COVID-19 pandemic (January 2020–April 2021), Russia-Ukraine war (February 2022–December 2022), and Iran-Israel conflict (October 2023–June 2024). Employing continuous wavelet transform, wavelet coherence, and partial wavelet coherence techniques, we decompose relationships across short-term, medium-term, and long-term horizons using daily data from Bloomberg. Descriptive statistics reveal fundamental differences between sustainable investments and digital assets: Clean Energy (mean: 0.0008, variance: 0.0004) and AI Index (mean: 0.0003, variance: 0.0002) demonstrate positive returns with low volatility, while NFT and DeFi tokens exhibit negative average returns and substantially higher volatility, with AAVE showing extreme kurtosis (773.27) and variance (0.0167). Wavelet coherence analysis reveals crisis-dependent and scale-specific patterns. During COVID-19, only short-term and medium-term coherence emerged, indicating transitory speculative relationships. The Russia-Ukraine war marked a structural shift, with AAVE demonstrating long-term coherence with Clean Energy, suggesting deeper market integration driven by energy market disruptions. The Iran-Israel conflict exhibited the most complex patterns, with broader long-term coherence across ENJ Coin, Theta, Synthetix, Maker, and SUPERf, indicating structural convergence between energy transition narratives and selected DeFi/NFT projects. These findings demonstrate that NFT/DeFi-sustainable investment relationships are crisis-dependent, scale-specific, and selectively integrative, with significant implications for portfolio diversification strategies and systemic risk monitoring during geopolitical crises.
Khan et al. (Mon,) studied this question.