On the digital geomagnetic observatory at Lunping, Taiwan

Abstract

A permanent Lunping Observatory was established by the author in 1965 at Lunping (25°00′ N; 121°10′ E), Taiwan. A set of Ruska magnetographs, a proton precession magnetometer and a GSI 1st Order Precession Magnetometer have been used to measure the hourly mean values of the geomagnetic three components, H, Z, D, and to determine the three hourly geomagnetic K indices from the daily magnetograms. The purpose of this paper is to show how a set of fluxgate digital magnetometers has been introduced at Lunping Geomagnetic Observatory to automate the routine work of the observatory to save the time spent for the tedious routine manual data production. To maintain the fluxgate digital magnetometers at their best conditions, it has been found that the temperatures of the sensors as well as the electronic parts of the fluxgate magnetometers have to be kept constant. Even though these temperatures have been kept constant, the aging effects of the sensors and electronic parts require absolute measurements of the geomagnetic field to obtain the accurate baseline values of the fluxgate magnetometers. The computer assisted determination of K indices is also presented and discussed.