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The Coupling of Atmospheric Electromagnetic Fields with Biological Systems
Published in Shoogo Ueno, Tsukasa Shigemitsu, Bioelectromagnetism, 2022
Tsukasa Shigemitsu, Shoogo Ueno
On a dry winter day, we have had the experience of receiving a violent electric shock to our fingertips when crossing a carpet, touching a metal doorknob or the body of a car, causing us to jump. We have also heard the sound of small sparks when taking off a synthetic fiber shirt. These are caused by static electricity generated by friction and discharged between your fingertips and the knob or car body, or between you and your synthetic fiber shirt. This kind of charging phenomena can also be observed in the open air. If the metal supported by insulating rods is placed at a hight of one meter above the ground, and measured its electric potential ranging from several tens of volts to several hundreds of volts can be observed on a sunny day. The higher the potential rises above the ground surface, the higher the value. When there are thunderclouds nearby, the potential is several times higher, ranging from several thousand volts to several tens of thousands of volts. This is due to the presence of electric fields, and positive and negative electrified molecules and particles, or air ions, in the atmosphere, which charge the metal plate. This kind of electrical phenomenon in the natural atmosphere is called atmospheric electricity.
Aurora borealis systems in the German-Russian world in the first half of the eighteenth century: the cases of Friedrich Christoph Mayer and Leonhard Euler
Published in Annals of Science, 2021
In the meantime, in the early 1740s, Anders Celsius and Olof Peter Hiorter highlighted the link between the aurora borealis and magnetism through a long series of observations of the irregular agitation of the magnetic needle during the aurora,68 a discovery that should have returned Halley’s system to the fore. However, from the beginning of the 1750s, with the discovery and exploration of atmospheric electricity, the electrical theory, developed independently by John Canton in England69 and Mikhail Vasilevich Lomonosov at the Imperial Academy of Sciences in St. Petersburg,70 overshadowed all previous hypotheses. It was not until the beginning of the twentieth century that the phenomenon was fully understood,71 borrowing from magnetic, solar and electrical theories.
The origins and early years of the Magnetic and Meteorological department at Greenwich Observatory, 1834-1848*
Published in Annals of Science, 2018
Airy was officially appointed Astronomer Royal with effect from October 1835, but he initially operated from Cambridge while he wound up his affairs there. He only moved to the Royal Observatory with his young family in mid-December. Yet more than a year before his arrival in Greenwich – though not before the Duke of Sussex had initially approached him about becoming Astronomer Royal – Airy received a letter from Samuel Hunter Christie dated (and postmarked) November 1834, that is clearly in reply to an enquiry from Airy. The author of the 1833 BAAS report urging the establishment of magnetic observations at Greenwich now expressed his pleasure that Airy was keen to take up magnetic observations. His letter is organized under four headings that seem to be based on questions asked by Airy: ‘The nature and immediate objects of the observations’; ‘The expence [sic] of the instruments’; ‘The degree of regularity and personal constraint necessary for the regular series’; and ‘The nature of the irregular observations’, the latter meaning aurorae and atmospheric electricity. Christie recommended regular observations of magnetic declination as the most immediately important object in this field, and suggested the method recently developed by Gauss as the best way of measuring this quantity. Christie offered to discuss the subject in more detail when on a visit to Cambridge the following week.69 That Airy, many months before his official appointment as Astronomer Royal, was making such detailed enquiries of Christie about the practicalities of magnetic observations is further evidence that he was independently interested in magnetic work.70
Condensational growth of water droplets in an external electric field at different temperatures
Published in Aerosol Science and Technology, 2020
Dmitrii N. Gabyshev, Alexander A. Fedorets, Otto Klemm
The interrelationships between atmospheric electricity and precipitation have been studied for centuries (Franklin 1751; Kelvin 1872; Foote 1878; Zeleny 1917). Electric fields typical for thunderstorm clouds affect the condensation processes in clouds (Isard 1977; Murino 1979; Warshavsky and Shchekin 1999; Vorob’ev and Malyshenko 2001; Amiri, Pourabadeh, and Khatibi 2002; Singh and Kumar 2003; Sharma 2010; Butt et al. 2011). Field strengths of about 105 V m−1 occur which accelerate the condensational growth of droplets (Gabyshev et al. 2019) specifically in the lower zone of the clouds, leading to a more rapid formation of precipitation (Shishkin 1954).