Decrease of intensity of ELF/VLF waves observed in the upper ionosphere close to earthquakes: A statistical study

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378289%3A_____%2F09%3A00330763" target="_blank" >RIV/68378289:_____/09:00330763 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Decrease of intensity of ELF/VLF waves observed in the upper ionosphere close to earthquakes: A statistical study

Original language description

We present results of a systematic study of intensity of VLF electromagnetic waves observed by the DEMETER spacecraft in the upper ionosphere (altitude 700 km). We focus on the detailed analysis of the previously reported decrease of wave intensity shortly before the main shock during the nighttime. Using a larger set of data (more than 3.5 years of measurements) and a newly developed data processing method, we confirm the existence of a very small but statistically significant decrease of wave intensity 0?4 hours before the time of the main shock at frequencies of about 1.7 kHz. It is shown that the decrease does not occur directly above the earthquake epicenter but is shifted about 2 degrees in the westward direction. Moreover, it is demonstrated that the decrease occurs more often close to shallower earthquakes and close to earthquakes with larger magnitudes, as it is "intuitively" expected, representing an additional proof of validity of the obtained results.

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

BL - Plasma physics and discharge through gases

OECD FORD branch

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Project

<a href="/en/project/GA205%2F06%2F1267" target="_blank" >GA205/06/1267: Low-frequency wave coupling of the atmosphere, ionosphere, and inner magnetosphere of the Earth</a><br>

Continuities

Z - Vyzkumny zamer (s odkazem do CEZ)

Publication year

2009

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Geophysical Research

ISSN

0148-0227

e-ISSN

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Volume of the periodical

114

Issue of the periodical within the volume

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Country of publishing house

US - UNITED STATES

Number of pages

10

Pages from-to

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UT code for WoS article

000264866000003

EID of the result in the Scopus database

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