Structural Persistence of the Coupled Earth Climate–Biosphere System Under Sustained Anthropogenic Forcing

Earth’s climate and biosphere are experiencing unprecedented anthropogenic forcing, yet whether these pressures have fundamentally reorganized the global Earth system remains unclear. In this study, we analyze the post-emergent structural behavior of the coupled Earth climate–biosphere system from 1850 to 2100 using a structure-aware, non-equilibrium diagnostic framework. Rather than focusing on regional outcomes or trend extrapolation, we examine the persistence of global organizational structure under strong forcing, stochastic variability, and symmetry-breaking perturbations. Across extensive control ensembles, the system converges to a stable, low-dimensional regime characterized by invariant topology, high causal density, moderate complexity, and strong self-similarity. Despite substantial anthropogenic pressure, no evidence is found for a completed global structural regime transition within the analyzed period. These results indicate that current Earth system risks are more likely to arise through abrupt phase transitions than through gradual structural degradation. This structural perspective reframes climate and biodiversity risk assessment, highlighting the importance of regime-level diagnostics and early-warning indicators for anticipating systemic change.