Polar Motion Data of International Polar Motion Service

Acting as the international polar motion measurement service(IPMS), this international joint measurement of longitude and latitude was carried out from 1962 to 1988. The coordinate values of polar motion(X, Y) and the change in the length of one day(L/D) were measured in this file. The IPMS central station(Mizusawa) recorded this data using diurnal values with the units of angular second and microseconds of time.