dot
Detailansicht
Katalogkarte GBA
Katalogkarte ISBD
Suche präzisieren
Drucken
Download RIS
Hier klicken, um den Treffer aus der Auswahl zu entfernen
Titel Low-frequency ionospheric sounding with Narrow Bipolar Event lightning radio emissions: regular variabilities and solar-X-ray responses
VerfasserIn A. R. Jacobson, R. Holzworth, E. Lay, M. Heavner, D. A. Smith
Medientyp Artikel
Sprache Englisch
ISSN 0992-7689
Digitales Dokument URL
Erschienen In: Annales Geophysicae ; 25, no. 10 ; Nr. 25, no. 10 (2007-11-06), S.2175-2184
Datensatznummer 250015932
Publikation (Nr.) Volltext-Dokument vorhandencopernicus.org/angeo-25-2175-2007.pdf
 
Zusammenfassung
We present refinements of a method of ionospheric D-region sounding that makes opportunistic use of powerful (109–1011 W) broadband lightning radio emissions in the low-frequency (LF; 30–300 kHz) band. Such emissions are from "Narrow Bipolar Event" (NBE) lightning, and they are characterized by a narrow (10-μs), simple emission waveform. These pulses can be used to perform time-delay reflectometry (or "sounding") of the D-region underside, at an effective LF radiated power exceeding by orders-of-magnitude that from man-made sounders. We use this opportunistic sounder to retrieve instantaneous LF ionospheric-reflection height whenever a suitable lightning radio pulse from a located NBE is recorded. We show how to correct for three sources of "regular" variability, namely solar zenith angle, radio-propagation range, and radio-propagation azimuth. The residual median magnitude of the noise in reflection height, after applying the regression corrections for the three regular variabilities, is on the order of 1 km. This noise level allows us to retrieve the D-region-reflector-height variation with solar X-ray flux density for intensity levels at and above an M-1 flare. The instantaneous time response is limited by the occurrence rate of NBEs, and the noise level in the height determination is typically in the range ±1 km.
 
Teil von