Streamflow Simulation and Interpretability Analysis in Multi-Climatic Basins Using Physics-Based and Data-Driven Hybrid Models
摘要
Differentiable modeling techniques have enabled end-to-end calibration of hydrological models and facilitated their integration with data-driven approaches. However, the potential of differentiable parameter learning across diverse climatic conditions remains underexplored, and a systematic evaluation of differentiable module replacement strategies remain limited. To address this, we develop a differentiable parameter learning model (D-HBV) based on the HBV-96 framework, in which Temporal Convolutional Network (TCN) and Convolutional Long Short-Term Memory (ConvLSTM) modules are incorporated to replace the runoff generation and routing components, respectively. Three hybrid models (D-T-M, D-H-C, and D-T-C) are constructed and applied to river basins spanning ten global climate types. Compared with the traditional HBV model, the D-HBV model improves NSE and KGE by 37.3% and 46.9%, respectively. The hybrid models achieve even greater gains, with D-T-C performing best, increasing NSE and KGE by 45.1% and 65.3%, and reducing RMSE by 41.4%, leading to more reliable reproduction of flood peaks, recession dynamics, and low-flow conditions. Interpretability analyses reveal that the TCN and ConvLSTM modules effectively capture nonlinear runoff responses and routing delays with strong physical consistency, allowing the model to reflect basin-specific runoff formation and flow concentration behaviors. The performance improvements of the hybrid models stem from their structural adaptability to basin-scale hydrological processes, with notable variation across climate zones. These findings underscore the importance of climate-aware neural integration design and demonstrate a promising pathway toward robust, transferable, and physically consistent streamflow simulation in a changing environment.