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Introduction to the Physics of Sprites, Elves and Intense Lightning Discharges
| Content Provider | Semantic Scholar |
|---|---|
| Author | Rycroft, Michael J. |
| Copyright Year | 2006 |
| Abstract | This chapter introduces the fundamentals of the subject, the laboratory for which is the Earth’s atmosphere. All of its important physical properties vary significantly with altitude; its electrical conductivity varies greatly with altitude and also with latitude. The modus operandi of the global atmospheric electric circuit, in part powered by thunderstorms, is outlined. Some observations of transient luminous events, which occur above certain energetic thunderstorm systems just after a strong lightning discharge (the effect of which is usually to take positive charge to the ground), are introduced and their characteristics mentioned. Different theoretical ideas that have been put forward to explain crucial aspects of these phenomena are introduced, and some relevant numerical simulations are briefly discussed. 1.1 Basic Properties of the Atmosphere 1.1.1 Global Scale Variations (Horizontal Scale greater than 10 km) The Earth’s atmosphere is bound gravitationally to our home planet. The pressure and density of the air decrease exponentially upwards from the surface, the scale height being ∼7 km (Rycroft, 2003). This scale height varies slightly through the atmosphere because it is not isothermal. Relatively, the hottest regions of the Earth’s neutral atmosphere are at its surface (global average temperature T=288 K, pressure p=1013 hPa, density =1.2 kg/m3), at the stratopause (∼250 K, near 50 km altitude) and in the thermosphere (above ∼110 km, from where the temperature rises rapidly up to ∼2000 K at ∼300 km altitude), depending on the phase of the cycle of solar activity, with successive maxima ∼11 years apart. About half of the atmosphere resides at and below an altitude of 5 km; 90% of the atmosphere lies below an altitude of ∼15 km. The pressure of the air at 32 km altitude is ∼1% of its surface value and, at 100 km altitude, it is about one millionth of its surface value. The coldest regions are at the top of the troposphere, termed the tropopause (at 18 km |
| Starting Page | 1 |
| Ending Page | 18 |
| Page Count | 18 |
| File Format | PDF HTM / HTML |
| DOI | 10.1007/1-4020-4629-4_1 |
| Alternate Webpage(s) | https://page-one.springer.com/pdf/preview/10.1007/1-4020-4629-4_1 |
| Alternate Webpage(s) | https://doi.org/10.1007/1-4020-4629-4_1 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
