ABSTRACT The study examines spatial and temporal changes in monthly precipitable water vapour (PWV) over Thailand using 37 years of monthly ERA-Interim re-analysis data (1981–2017). PWV from ERA-Interim data was compared with that derived from radiosonde observations at four stations and it was shown to have an average root-mean-square error and mean bias error of 0.264 cm and −0.137 cm, respectively. Then, PWV from ERA data was used to estimate spatial patterns of monthly average PWV for the winter (Nov, Dec, Jan), summer (Feb, Mar, Apr, May) and rainy (Jun, Jul, Aug, Sep, Oct) seasons as well as the yearly averages. Statistically significant increases in PWV are found in the rainy season which has been related to the West Pacific index (WP). A second statistically significant increasing trend is found over the southern half of Thailand during the winter season which could be influenced by changes related to the Siberian High pressure.

中文翻译：

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泰国可降水水汽的时空变化

摘要 该研究使用 37 年的月度 ERA-Interim 再分析数据（1981-2017 年）检查了泰国每月可降水量水汽 (PWV) 的空间和时间变化。来自 ERA-Interim 数据的 PWV 与来自四个站点的无线电探空仪观测结果的 PWV 进行了比较，结果显示其平均均方根误差和平均偏差误差分别为 0.264 cm 和 -0.137 cm。然后，来自 ERA 数据的 PWV 用于估计冬季（11 月、12 月、1 月）、夏季（2 月、3 月、4 月、5 月）和雨天（6 月、7 月、8 月、9 月、10 月）的月平均 PWV 空间模式季节以及年度平均值。在与西太平洋指数 (WP) 相关的雨季中发现 PWV 的统计显着增加。