Water vapor scale height is an important parameter that reflects the vertical distribution of water vapor and also a key parameter that is usually used to make height correction in GNSS zenith wet delay and tropospheric tomography .Based on the spectral analysis of the time series of water vapor scale height from2006 to 2012 ,it is found that the water vapor scale height shows an annual and a semi‐annual variation in time .So ,the trigonometric functions with an annual and a semi‐annual cycle are used to express the time variation of water vapor scale height .And then the European Centre for Medium‐range Weather Forecasting (ECMWF) data are used to fit the coefficients of the trigonometric functions at 1°× 1° grid points on a global scale .By these methods ,a global water vapor scale height model GSH is firstly established ,which considers both the time and geographic variations of water vapor scale height .By taking radiosonde data as reference ,the GSH model has bias of -0 .19 km and rootmean square error (RMSE) of 1 8.1 km;by taking ECMWF data as reference ,the GSH model has bi as of 0 0.4 km and RMSE of 15.2km.TheGSHmodel showsarelativelyevenaccuracyonaglobal scale,andcouldservethestudyof GNSS meteorology and provide reference values of water vapor scale height for related meteorological researches .%水汽标高是一个反映水汽垂直分布特征的参数，也是全球导航卫星系统（global navigation satelli te system ，GNSS）对流层天顶湿延迟改正和GNSS水汽层析中的一个辅助参数。本文对2006—2012年水汽标高的时间序列进行频谱分析，发现水汽标高在时间上呈现出年周期和半年周期变化，因此利用包含年周期和半年周期的三角函数来表达水汽的时变规律，然后利用欧洲中尺度天气预报中心（European Centre for Medium‐range Weather Forecasting ，ECMWF）的数据在全球1°×1°的格网点上分别拟合了三角函数的系数。通过上述方法首次构建了一个全球适用的水汽标高模型GSH ，该模型既体现了水汽标高的时变特性又考虑了其地理差异。以无线电探空数据为参考，GSH具有－01．9 km的偏差（bi as）和18．1 km的均方根误差（root mean square error ，RMSE）；以ECMWF数据为参考，GSH具有00．4 km的bi a s和15．2 km的RMSE。GSH整体上表现出了比较稳定的精度，可服务于GNSS气象学研究，也可为其他相关气象研究提供水汽标高参考。
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