Abstract The identification of storm tracks that generate the annual maximum floods and the quantification of their air-moisture content is proposed to understand better the atmospheric generation processes of floods in Spain, as well as their decreasing trends identified previously. In this work, the role of the atmospheric component on hydrological changes on Spain by using storm track data generated by the hybrid single particle Lagrangian integrated trajectory model (HYSPLIT) is examined. Storm tracks associated with annual maximum flood series from 14 streamflow gauges located across Spain are obtained by using NCEP/NCAR Reanalysis data. They are classified into five clusters through use of the K-means algorithm. It was also shown that the use of five clusters was able to reproduce the five major types of storms identified in Spain reported in the literature. The posterior grouping of the five associated storm types into two bigger groups (Oceanic and Continental storms), led to a coherent seasonal and spatial behaviour of hydrological regimes. For some gauges, it was observed that distinct flood statistics, such as mean and variance, differ significantly as a result of atmospherically distinct generation processes, suggesting that local annual maximum flood series may be non-homogeneous as a result of contrasting atmospheric generation processes. By means of logistic regression, it is estimated that the probability of occurrence of Oceanic storms reduced significantly in the Spanish Atlantic region along the studied period. Furthermore, the existence of low-frequency cycles introduces significant variation in the occurrence of storm types in the country, with them being much more frequent during the period 1975–1979, while Oceanic storms were more frequent during the 1983–1987 and 1996–1999 periods. Those storms classified as Continental are observed in 59.3% of the studied cases, while those termed Oceanic in 40.7%. Continental storms also contribute with more moisture in the studied cases, that is to say, 63.1% of total moisture content, while Oceanic storms contributed with 36.9%.

中文翻译：

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西班牙不同类型风暴路径与洪水趋势之间的联系

摘要 建议识别产生年度最大洪水的风暴轨迹及其空气水分含量的量化，以更好地了解西班牙洪水的大气生成过程，以及之前确定的下降趋势。在这项工作中，通过使用混合单粒子拉格朗日综合轨迹模型 (HYSPLIT) 生成的风暴轨迹数据，研究了大气成分对西班牙水文变化的作用。使用 NCEP/NCAR 再分析数据获得与来自西班牙各地的 14 个流量测量仪的年度最大洪水系列相关的风暴轨迹。通过使用 K-means 算法将它们分为五个集群。还表明，使用五个集群能够重现文献中报告的西班牙确定的五种主要风暴类型。五种相关风暴类型的后部分组为两个更大的组（海洋和大陆风暴），导致水文状况的季节性和空间行为一致。对于某些仪表，观察到不同的洪水统计数据，例如平均值和方差，由于大气不同的生成过程而显着不同，这表明由于大气生成过程的对比，当地年度最大洪水系列可能是非均质的。通过逻辑回归，估计在研究期间，西班牙大西洋地区发生海洋风暴的概率显着降低。此外，低频周期的存在导致该国风暴类型发生的显着变化，它们在 1975-1979 年期间更为频繁，而海洋风暴在 1983-1987 和 1996-1999 期间更为频繁。在 59.3% 的研究案例中观察到了那些被归类为大陆的风暴，而那些被称为海洋的风暴则占 40.7%。在研究的案例中，大陆风暴也贡献了更多的水分，也就是说，占总水分含量的 63.1%，而海洋风暴贡献了 36.9%。在 59.3% 的研究案例中观察到了那些被归类为大陆的风暴，而那些被称为海洋的风暴则占 40.7%。在研究的案例中，大陆风暴也贡献了更多的水分，也就是说，占总水分含量的 63.1%，而海洋风暴贡献了 36.9%。在 59.3% 的研究案例中观察到了那些被归类为大陆的风暴，而那些被称为海洋的风暴则占 40.7%。在研究的案例中，大陆风暴也贡献了更多的水分，也就是说，占总水分含量的 63.1%，而海洋风暴贡献了 36.9%。