基于GBDT算法的海河流域TRMM卫星降水产品降尺度研究  

Downscaling of TRMM Satellite Precipitation Products for the Haihe River Basin Based on GBDT Algorithm

作　　者：苗昌盛 Miao Changsheng(Zhangjiakou Research Centre for Hydrological Survey of Hebei Province,Zhangjiakou 075000,Hebei)

机构地区：[1]河北省张家口水文勘测研究中心,河北张家口075000

出　　处：《陕西水利》2025年第2期11-14,共4页Shaanxi Water Resources

摘　　要：准确获取高分辨率的地面降水信息,对于流域水文模拟、作物生长模拟等研究具有重要意义。针对现有TRMM卫星产品多存在低空间分辨率缺陷,以海河流域为研究区,提出一种基于GBDT(梯度提升决策树)算法的TRMM(热带降雨观测计划)卫星降水产品降尺度新方法。该方法将TRMM数据与多源辅助数据(地形、土地覆盖等)相融合,构建出高维输入向量,基于GBDT回归模型预测每个高分辨率网格点上的降水量,从而实现降尺度。研究结果表明:(1)GBDT算法具有良好非线性映射能力,在海河流域的降尺度精度显著提高;(2)经过降尺度处理后,TRMM产品的空间分辨率由0.25°提高到4 km,与地面站点观测的拟合系数R2可达到0.73;(3)高分辨率产品较好刻画出了海河流域降水的空间异质特征,揭示了地形、植被等地理要素对降水分布格局的重要影响。该研究可为制取高质量卫星降水数据提供了新思路和技术路线。Accurately obtaining high-resolution ground precipitation information is crucial for studies such as basin hydrological modeling and crop growth simulation.Addressing the low spatial resolution deficiency common in existing TRMM satellite products,this study proposes a new downscaling method based on the GBDT algorithm for TRMM satellite precipitation products within the Haihe River Basin.This method integrates TRMM data with multi-source auxiliary data(such as topography,land cover,etc.)to construct high-dimensional input vectors.The GBDT regression model is then used to predict precipitation amounts at each high-resolution grid point,thereby achieving downscaling.The research results show that:The GBDT algorithm possesses excellent nonlinear mapping capabilities,significantly improving downscaling accuracy within the Haihe River Basin;After downscaling processing,the spatial resolution of TRMM products was enhanced from 0.25°to 4km,with a coefficient of determination(R²)of up to 0.73 when compared to ground station observations;③Thehigh-resolutionproductaccurately representsthespatial heterogeneity ofprecipitationintheHaiheRiver Basin,revealing the significant impact of geographic elements such as terrain and vegetation on precipitation distribution patterns.This study provides a new approach and technical route for generating high-quality satellite precipitation data.

关 键 词：TRMM卫星 降水 降尺度 梯度提升决策树 海河流域 

分 类 号：P332.1[天文地球—水文科学]