站点气温格点化方法在贵州区域的研究与应用

Research Application of Air Temperature Gridded Analysis Method in Guizhou Province

利用2019年1—12月国家气象信息中心实况格点资料、贵州地面观测站资料以及ECMWF 2 m气温起报场资料,讨论了相同插值方案下站点数对空间分布的反演效果以及相同测站数下不同插值方案的表现,同时对国家气象信息中心实况格点场进行检验,并对本地建立的气温格点分析场进行初步评估。结果表明:相同的插值方案下,站数越多越能反映要素场的实际分布状态;基于贵州特殊地形,在相同站数下双线性插值法优于邻域法;通过对国家气象信息中心实况格点分析场评估,日最高、最低气温在贵州区域均存在明显误差,其平均绝对误差分别为1.6℃与1.1℃左右,平均RMSE分别达2.2℃与1.6℃。采用Cressman方案对离散观测资料重建的本地化气温格点分析场进行评估,其最高、最低气温平均绝对误差降至0.2℃与0.1℃左右,大幅度降低了与测站观测值的差异,基本可以代替国家气象信息中心下发的气温格点分析场,并将为今后贵州省业务或研究工作中格点预报的客观订正提供新的更符合实际的参考。

Based on the National gridded real-time observation datasets by the National Meteorological Information Center of CMA,observation data of Guizhou Province and the 2 m temperature forecast data of ECMWF between January and December in 2019.The influence of different stations on spatial distribution inversion under the same interpolation scheme were evaluated,and the results of different interpolation schemes in Guizhou province were discussed,also the gridded analysis field of the National Meteorological Information Center and the local rebuild real temperature gridded field were evaluated.The results show that the more stations,the better the distribution of real the factor field could be reflected while under the same interpolation method;Bilinear interpolation method was better than neighborhood interpolation method in the same stations under the special terrain of Guizhou;According to the evaluation of the real-grid analysis field of the National Meteorological Information Center,the maximum and minimum temperatures have obvious errors in Guizhou Province,the average absolute error was around 1.6℃and 1.1℃,and the mean RMSE was around 2.2℃and 1.6℃respectively.The rebuild temperature real filed was used to observation data under the Cressman scheme,the mean absolute error of the maximum and minimum temperatures decreased to about 0.2℃and 0.1℃respectively,which greatly reduced the error to the observation values of the stations.Generally,the rebuild temperature gridded data in Guizhou region can basically replace the National Meteorological Information Center of CMA grid real field,and will provide a new and more practical reference for the objective correction of grid forecast and research work in the future in Guizhou province.