Ionosphere 5 : The zone of the atmosphere, from about 70 km to 500 km, in which charged particles, ions and electrons are formed by photo-ionization under the effect of the sun's radiation
By M. Debacker, B. Domres, Walter Hays, J. de Boer, Prehospital and Disaster Medicine, Disaster Terminology, Glossary of New Concepts in Disaster Medicine, USA 2002, http://www.eird.org/isdr-biblio/PDF/Prehospital%20 and%20disaster%20medicine.pdf, (D/DM - Amer) {831}