During the Gjøa and Discovery expeditions (1901–1906), weak geomagnetic signatures were observed simultaneously with visual polar cap auroras.  Main types are transpolar arcs, poleward-moving substorm arcs, and Sun-aligned arcs.  The first two are infrequent, while the last one occurs often. They appear like the regular magnetic solar Sq variation.  It is suggested that they are embedded in polar rain and dependent on the density and energy of photoelectrons.

The foundation of the Societas Meteorologica Palatina was the most important step toward a physical consideration of meteorology. The organization was exemplary for later observational networks. The data were printed in 12 volumes of ephemerides, being for a long time the most important and reliable database for scientific research. This data pool is not only of historical interest, but it is also used in modern research in many fields.

This paper describes the details of the Japan's participation in the EISCAT Radar Scientific Association as the 7th associate country approved in 1995, emphasizing strong collaboration with Norwegian scientists and the EISCAT Radar Scientific Association towards the realization of the Svalbard second antenna. Also described is a brief summary of Japanese EISCAT-related scientific achievement, comprehensive scientific collaborations so far between Japan and Europe, and hopes for EISCAT_3D.

The Madden–Julian Oscillation (MJO) is an important phenomenon in tropical meteorology first discovered in the early 1970s by Roland Madden and Paul Julian. In this paper, Roland Madden relates the story of developments in theory, observations, and analysis techniques in the 1960s that led to that discovery.

We present the history of how and why a high-power radio wave transmitter facility with large antenna arrays was built in northern Norway in the 1970s with the aim of injecting radio waves into the auroral ionosphere. The facility has conducted fundamental research on plasmas, by heating electrons and exciting plasma waves in the ionosphere; the effects of these experiments have been measured using a host of other instruments, such as incoherent scatter radars, radio receivers, and cameras.