Abstract. The Societas Meteorologica Palatina arranged the first international meteorological network in a modern sense, being in operation between 1781 and 1792 during the last period of enlightenment. A total of 39 stations contributed observations. The original aim was to investigate influences of the moon and planets on the atmosphere. Instruments were provided free of charge; a physically very advanced instruction guaranteed reliable observational results, and the data collected at 3 different hours per day were printed at high cost in the Ephemerides Societatis Meteorologicae Palatinae (denoted Ephemerides hereafter) of Mannheim. This wealth of data has become a famous treasure trove for scientists and has been used later very often for climatic studies, for climatic comparisons of different locations in textbooks, for overcoming wrong but generally accepted or even outdated (e.g. scholastic) views; for finding new explanations for meteorological phenomena, and for studying extremes of meteorological parameters. Even in modern times, the data were evaluated and used to reconstruct historical weather maps. Although, meanwhile, some problems of the historical instruments have been recognized, most of the conclusions are still basically correct. The data were also used for verifying geomagnetic models or proxy data from tree-ring analysis. This network stimulated many scholars for special meteorological studies, and it was attractive for new stations to join the network. The early death of the meteorological secretary Johann Jakob Hemmer and the Napoleonic Wars brought about the end of the project. Nevertheless, many of the stations continued the observations using the available instruments.

Abstract. James Cook's second voyage to the South Seas, undertaken to settle the question regarding the existence or otherwise of the “Great Southern Continent” (Terra Australis Incognita), involved two vessels, the Resolution and Adventure. The Board of Longitude appointed two astronomers from the Royal Observatory, Greenwich, to the voyage, William Wales and William Bayly, respectively, one to each vessel. They were instructed, in addition to their astronomical duties, to observe the height and time of the tides. To this end, Bayly and Wales fabricated tide gauges and conducted timed measurements of sea level during their stopovers in New Zealand during 1773. This paper reviews those tidal observations, the first of their kind in New Zealand, using modern understanding of the tide, assuming that no significant change in the tidal regime at each location has taken place during the intervening period. When compared to the predicted (hindcast) astronomical tide, the majority (80 %) of the observed ranges and times agreed within 20 cm and 30 min, respectively. Whilst their observations have little scientific value today (other than indicating the quality attainable in the late 18th century), Bayly and Wales can not only rightfully lay claim to making New Zealand's first tide gauge measurements but also, as far as it possible to ascertain, be justifiably proud of the quality of their endeavours.

Abstract. During 4 decades, from 1950 to 1990, atmospheric electricity measurements as well as other environmental measurements were made by Reinhold Reiter at several sites close to Garmisch-Partenkirchen. The quantities determined included the atmospheric potential gradient, the vertical current, and the ion concentrations. Observations made at the Mount Wank site (47∘30′ N, 11∘09′ E; 1780 m) from 1 August 1972 to 31 December 1983 are available in digital form.

Abstract. In Sect. 1, the original planning of Japanese Svalbard IS (incoherent scatter) radar with phased-array antennas is described. In 1988, this plan was proposed as one of the major projects for the forthcoming Solar–Terrestrial Environment Laboratory, Nagoya University, Japan, to be reorganized by the Research Institute of Atmospherics at Nagoya University. On the other hand, in 1989, UK scientists proposed a plan of polar cap radar with parabolic dish antennas in Longyearbyen to the EISCAT (European incoherent scatter) Council. In Sect. 2, the circumstances leading to Japan's participation in the EISCAT Scientific Association, with details of its processes with strong collaborations with Norwegian scientists and the EISCAT Scientific Association are described. In 1995, Japan participated EISCAT Scientific Association as the seventh member country with funds contributing to the second dish antenna of the EISCAT Svalbard Radar. In Sect. 3, a summary of the EISCAT-related achievement by Japanese scientists is described, where major interests are the lower thermosphere wind dynamics, the magnetosphere–ionosphere–thermosphere coupling, characteristics, and driving mechanisms of ion upflow, electrodynamics of current, electric field and particles, characteristics and production mechanisms of auroras, such as pulsating aurora, and aurora tomography. In Sect. 4, a summary of the scientific collaborations between Japan and Europe, particularly those between Japan and Norway, and hopes for the forthcoming EISCAT_3D and further collaboration with EISCAT community are described.

Abstract. Shortly after the introduction of the physical unit for the magnetic field in 1832 and the invention of the bifilar apparatus in 1837, both being extraordinary scientific achievements that took place in Göttingen, the Clementinum observatory in Prague became one of the first places where systematic observations of the horizontal intensity of the geomagnetic field began. Karl Kreil was decisively responsible for this. In this paper, we focus on the very beginnings of geomagnetic observations in Prague, dating from the middle of 1839. We describe the archival materials with data that exist from that time, how the main instrument for observing magnetic storms – the bifilar magnetometer – worked and how it was calibrated, and the first magnetic survey in Bohemia. This study indicates the importance of historical geomagnetic observation materials to modern science, such as space weather research.

Abstract. The measurement series of the three geomagnetic observatories Potsdam, Seddin and Niemegk spans 130 years, starting in 1890. It is one of the longest, almost uninterrupted series of recordings of the Earth's magnetic field. Data users frequently emphasise the high quality of the data and their significance for geomagnetic base research. Very well known outstanding geomagnetism scientists, such as Max Eschenhagen, Adolf Schmidt, Julius Bartels, Gerhard Fanselau and Horst Wiese, directed the observatories during their existence. This paper describes the history of the Seddin Observatory, which was in operation from 1907 until 1932.

Abstract. The Australian Bureau of Meteorology (http://www.bom.gov.au/climate/mjo, last access: 9 February 2023) states that “The Madden–Julian Oscillation (MJO) is a major fluctuation in tropical weather on weekly to monthly timescale. The MJO can be characterized as an eastward moving `pulse' of cloud and rainfall near the Equator that typically recurs every 30 to 60 days.” Early descriptions of the MJO were contained in two papers by Madden and Julian (1971, 1972). This paper relates the story of developments in tropical meteorology in the 1960s that led to those two papers. The decade saw the first unambiguous identification of large-scale, theoretically predicted, tropical waves. Spectral analysis was used effectively by researchers to link observations with the theoretically expected features of these waves. At the same time, longer time series of observations, faster computers, and an algorithm designed to speed up Fourier transforms, vital for spectral analysis, all became available. These developments set the stage for the oscillation to be recognized.

Abstract. The measurement series of the three geomagnetic observatories Potsdam, Seddin and Niemegk spans more than 130 years, starting in 1890. It is one of the longest, almost uninterrupted series of recordings of the Earth's magnetic field. Data users frequently emphasise the high quality of the data and their significance for geomagnetic base research. Very well known outstanding geomagnetism scientists, such as Max Eschenhagen, Adolf Schmidt, Julius Bartels, Gerhard Fanselau and Horst Wiese, directed the observatories during their existence. This paper describes the history of the Potsdam Observatory, which was in operation from 1890 until 1928.

Abstract. This article describes the international seismological cooperation at the beginning of the last century and how this cooperation changed due to World War I (WWI). These changes were the direct reasons leading to the foundation of the Deutsche Seismologische Gesellschaft (DSG, German Seismological Society) in 1922, which changed its name to the Deutsche Geophysikalische Gesellschaft (DGG, German Geophysical Society) 2 years later. The second part of the article shortly describes the further development of the relationship between German geophysicists and their international colleagues until the beginning of World War II (WWII).