Electrical phenomena that occur in the atmosphere, excluding the phenomena involved in the ionosphere. Even under normal conditions (i.e. in the absence of thunderstorm activity) the upper atmosphere has a substantial positive space charge relative to the Earth's surface. Various mechanisms (such as cosmic rays) act to ionize atmospheric atoms and molecules, and in regions of fine weather, positive ions move down towards the negatively charged surface, whereas negative ions migrate upwards. There is also a substantial flow of current upwards that accompanies the downward transfer of charge in thunderstorms. See also blue jet; elf; gigantic jet; lightning; St Elmo's fire; sprite.
Subjects: Meteorology and Climatology.