Special issue  

The Széchenyi István Geophysical Observatory, also known as the Nagycenk Geophysical Observatory (NCK), is the only measurement site in Hungary where atmospheric electricity (AE) measurements have been made continuously since 1961. Quasi-continuous records of electrical potential gradient (PG) and Schumann resonances (SRs) from NCK are among the longest time series of their kind in Europe. This paper commemorates the efforts of people who established and managed AE measurements at NCK.

Eskdalemuir Observatory opened in 1908, sited remotely for magnetically quiet conditions. Continuous atmospheric potential gradient (PG) recordings began in 1911, using a Kelvin water dropper electrograph. Notable scientists who worked with atmospheric electricity at Eskdalemuir include Lewis Fry Richardson and Gordon Dobson. The PG measurements continued until 1981. The methodologies employed are described to help interpret the monthly data now digitally available.

Environmental measurements were undertaken by Reinhold Reiter (1920–1998) around Garmisch-Partenkirchen in the Bavarian Alps for 4 decades. This included measurement sites on the Zugspitze and Wank mountains as well as the use of an instrumented cable car between the Eibsee and the Zugspitze summit. The Mount Wank site operated between 1 August 1972 and 31 December 1983, and the hourly data values – including atmospheric electricity quantities – for this site have been recovered.

Lerwick Observatory in Shetland has recently celebrated its centenary. Measurements of atmospheric electricity were made at the site between 1925 and 1984. The instruments and equipment used for this are discussed and the value of the measurements obtained assessed. A major aspect of the atmospheric electricity work was explaining the dramatic changes which followed the nuclear weapons test period. Although less well known, there are strong parallels with the discovery of the ozone hole.

The early 20th century voyages of the Carnegie – a floating geophysical observatory – revealed the daily rhythm of atmospheric electricity. Combined with ideas from Nobel Prize winner C. T. R. Wilson, the Carnegie curve helped answer a fundamental question, from the time of Benjamin Franklin, about the origin of Earth's negative charge. The Carnegie curve still provides an importance reference variation, and the original data, explored further here, have new relevance to geophysical change.