Eigen microstate analysis unveils climate dynamics

The Earth’s climate operates as a complex, dynamically interconnected system, driven by both anthropogenic and natural forcings and modulated by nonlinear interactions and feedback loops. This study employs a theoretical framework and the Eigen Microstate (EM) approach of statistical physics to examine global surface temperature variations since 1948, as revealed by a global reanalysis. We identified EMs significantly correlated with key climate phenomena such as the global monsoon system, tropical climates, and El Niño. Our analysis reveals that these EMs have increasingly influenced global surface temperature variations over recent decades, highlighting the critical roles of hemispheric differences, land-sea contrasts, and tropical climate fluctuations in a warming world. Additionally, we used model simulations from more than 10 Coupled Model Intercomparison Project Phase 6 (CMIP6) under three future climate scenarios to perform a comparative analysis of the changes in each EM contribution. The results indicate that under future warming scenarios, tropical climate fluctuations will become increasingly dominant, while traditional hemispheric and monsoonal patterns may decline. This shift underscores the importance of understanding tropical dynamics and their impact on global climate from a physics-based perspective. Our study provides a new perspective on understanding and addressing global climate change, enhancing the theoretical foundation of this critical field, and yielding findings with significant practical implications for improving climate models and developing effective mitigation and adaptation strategies.