Application of the Regression-Augmented Regionalization Approach for BTOP Model in Ungauged Basins

Ten years after the Predictions in Ungauged Basins (PUB) initiative was put forward, known as post-PUB era (2013 onwards), reducing uncertainty hydrological prediction ungauged basins still receives considerable attention. This integration or optimization of traditional regionalization approaches is an effective way to improve river discharge simulation basins. In Jialing River, southwest China, regression equations model parameters and watershed characteristic factors were firstly established, based on block-wise use TOPMODEL (BTOP). paper explored application twelve that combined with spatial proximity, physical similarity, regression-augmented approach five target The results showed proximity performs best studied basins, while satisfactory well, indicating a good potential for However, approach, number considered equation impacts simulated effect, implying determination optimal set by parameter crux strength may also be influencing factor. These findings provide meaningful information establish parametric transfer equation, well references data-sparse regions BTOP model. Future research should address classification donor under distance between reference basin basin, build adopted each group, further explore this approach’s potential.