Abstract A gridded precipitation dataset derived from the high-density rain gauge network of the Ebro River Basin Authority is used to evaluate the performance of Integrated Multi-satellitE Retrievals for GPM (IMERG) level-3 estimates. Although aggregated values compare well, several differences are found between climate regions. The research investigates the role of orography and gauge density on IMERG performance. There are important discrepancies over un-instrumented areas in the Pyrenees (R2 = 0.31) but the correlation dramatically increases (R2 > 0.71) when at least one rain gauge is available for calibration, even in complex, high-altitude terrain (>1500 m). IMERG overestimates precipitation at both lower altitudes (

中文翻译：

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埃布罗河流域（西班牙）IMERG 降水估计的地形偏差：雨量计密度和高度的影响

摘要 来自埃布罗河流域管理局高密度雨量计网络的网格降水数据集用于评估综合多卫星检索 GPM (IMERG) 3 级估计的性能。尽管汇总值比较好，但在气候区域之间发现了一些差异。该研究调查了地形和规范密度对 IMERG 性能的影响。比利牛斯山脉的未检测区域存在重要差异 (R2 = 0.31)，但当至少有一个雨量计可用于校准时，即使在复杂的高海拔地形 (>1500 m) 中，相关性也会显着增加 (R2 > 0.71) ）。IMERG 高估了两个低海拔地区的降水（