Accession Number : ADA573900


Title :   Interaction with the Lower Ionosphere of Electromagnetic Pulses from Lightning: Heating, Attachment, Ionization, and Optical Emissions


Descriptive Note : Doctoral thesis


Corporate Author : STANFORD UNIV CA DEPT OF ELECTRICAL ENGINEERING


Personal Author(s) : Taranenko, Yuri N


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a573900.pdf


Report Date : 25 Sep 1993


Pagination or Media Count : 108


Abstract : A typical lightning discharge produces an intense 20 gigawatt electromagnetic (EM) pulse of 50 to 150 s duration. A significant portion of this energy propagates upward where it interacts with the ambient electrons in the collisional lower ionosphere. In the present work the Boltzmann kinetic equation for electrons and Maxwell's equations for the EM fields are self-consistently solved to simulate the interaction of lightning radiated EM pulses with the lower ionosphere. Results indicate that attachment, ionization, and optical emissions produced in this interaction are sufficient to explain 'early' subionospheric VLF signal perturbations and airglow brightening observed simultaneously with lightning. This model also provides the basis for the quantitative evaluation of a wide variety of electrodynamic and chemical processes in the ionosphere which occur in response to the energy released in lightning discharges. Under nighttime conditions, individual pulses with peak amplitudes of 10-20 V/m (normalized to 100 km free space distance) produce changes in electron density of 1-30% of the ambient while a sequence of such pulses leads to more than 100 % modification at altitudes between 85 and 92 km.


Descriptors :   *ELECTRODYNAMICS , *ELECTROMAGNETIC PULSES , *ELECTROMAGNETISM , *KINETIC THEORY , *OPTICAL PROPERTIES , BOLTZMANN EQUATION , CHEMICAL REACTIONS , ELECTRONS , EMISSION , ENERGY , INTERACTIONS , IONOSPHERE , MAXWELLS EQUATIONS , SIGNALS , TEST AND EVALUATION , THESES


Subject Categories : Electromagnetic Pulses


Distribution Statement : APPROVED FOR PUBLIC RELEASE