Air-ground current - Air-ground current

...The atmosphere is not a perfect insulator, but has the property of conducting a very small amount of electricity. On a clear, windless day, the ground is negatively charged, and positive charges are distributed in the upper atmosphere, resulting in a vertical distribution of electric potential in the atmosphere, higher at the top and lower at the bottom. This is called the "atmospheric electric field," and the electric current (3× ^10-13 A per m2) that flows from the upper layers to the ground is called the "air-ground current." The atmosphere is very weak but has electrical conductivity because charged particles called "atmospheric ions" exist in the atmosphere and move according to the electric potential difference. ...

*Some of the terminology explanations that mention "air-ground current" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…また大気は完全な絶縁体ではなく，ごくわずかであるが電流を通す性質をもち，晴天無風のとき，地表は負に帯電し，上層の大気中には正電荷が分布し，大気中では垂直に，上方が高く下方が低い電位の分布が生じている。これを〈大気電界〉とよび，このため上層から地表に向かって流れる電流(1m2当り3×10^－13A)を〈空地電流〉という。大気が非常に微弱であるが導電率をもつのは，〈大気イオン〉とよばれる荷電粒子が大気中に存在し，電位差に応じて移動するためである。…

※「空地電流」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報