资源环境科技发展态势分析平台

Cao et al. (2019, ) proposed a modified particle filter-based data assimilation method with a local weighting procedure (MPFDA-LW) for a two-dimensional hydrodynamic model (HydroM2D) in dam-break flood simulation. The MPFDA-LW method intends to take into account the spatial-temporal variability of the Manning coefficient to improve the performances of the HydroM2D model. Although Cao et al. (2019, ) correctly pointed out that the Manning coefficient may spatially and temporally vary during a flooding process, the approach they handled this issue was inappropriate because they arbitrarily adjusted model parameters without considering the physical mechanism behind them. In addition, contrary to what the authors claimed, the proposed MPFDA-LW method can barely improve the prediction of flooding processes, because changing the Manning coefficient at several computational grid cells has little influence on the overall flooding processes.