On the calculation of Hough functions for resolving atmospheric thermal tidal structure
面向大气热力潮汐结构分析的Hough函数计算

As the functions that characterize the fundamental structures of global scale atmospheric waves, Hough funtions provide a physically based means in analyzing the dynamics atmospheric tides, and are also used as an numerical tool with enhanced efficiency in the integration of atmospheric models. This paper introduces our development in the calculation of Hough functions based upon Laplace's tidal equation. The framework of the calculation and the details of the procedures are described. The Eigen values and the Hough functions associating to each of the 39 tidal components, i.e., that include the components falling in three primary frequencies, viz., diurnal, semidiurnal and terdiurnal, and in zonal wavenumber range -6, 6], are all calculated. As examples, the results of the Hough functions associating to the migrating diurnal and semidiurnal tides are presented here to show the correctness in the structure of these functions. And the results of the corresponding Eigen values show that substantial accuracies in these values are maintained, which suggests that the cuurent results are sufficiently applicable for conventional applications.