潮汐非调和常数是一组用来描述港口潮汐特征的数据,应当从长期观测的高、低潮时间及高度中统计得出。然而在只有短期记录的情况下,由于潮汐存在着长周期的变化,直接统计得出的结果会出现相当大的误差。因此,在只有短期验潮的港口,人们常常利用潮汐的调和常数间接计算非调和常数;而调和常数则可利用短期记录求得,不会带来严重的误差。各国使用的潮汐非调和常数计算方法不尽相同。在我国,郑交振同志编著的《实用潮汐学》一书中全面地介绍了 Tidal unharmonic constants are a set of data used to describe the tidal characteristics of a port and should be derived from the high and low tide times and altitudes of long-term observations. However, in the case of only short-term records, there are considerable errors in the results of direct statistics due to the long-period tidal changes. Therefore, in the short-term tide of the port, people often use the harmonic constant of the tide to calculate the non-harmonic constant; and the harmonic constant can be calculated using short-term records will not bring serious errors. The tide non-harmonic constants used in various countries are calculated differently. In our country, Comrade Zheng Jiazhen compiled a book entitled Practical Tide Studies