Role of parametric decay instabilities in generating ionospheric irregularities

Journal Article · Sat Jan 01 04:00:00 EST 1983 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA088iA01p00417· OSTI ID:6034706

Kuo, S P; Cheo, B R; Lee, M C

We show that purely growing instabilities driven by the saturation spectrum of parametric decay instabilities can produce a broad spectrum of ionospheric irregularities. The threshold field Vertical BarE/sub th/Vertical Bar of the instabilities decreases with the scale lengths lambda of the ionospheric irregularities as Vertical BarE/sub th/Vertical Barproportionallambda/sup -2/ in the small-scale range (<15 m) but becomes an increasing function as Vertical BarE/sub th/Vertical Barproportionallambda in the large-scale range. The minimum threshold field (approx.2 mV/m) occurs at lambdaapprox.20 m. The growth rate ..gamma.. of the instabilities maximizes at lambdaapprox.6 m and decreases drastically as ..gamma..proportionallambda/sup -2/ with scale lengths larger than a few kilometers. The excitation of kilometer-scale irregularities is strictly restricted by the instabilities themselves and by the spatial inhomogeneity of the medium. These results are drawn from the analyses of four-wave interaction. Ion-neutral collisions impose no net effect on the instabilities when the excited ionospheric irregularities have a field-aligned nature.

• Research Organization: Polytechnic Institute of New York, Long Island Center, Farmingdale, New York 11735
• OSTI ID: 6034706
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 88:A1; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
&amp; Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COLLISIONS
DECAY INSTABILITY
EARTH ATMOSPHERE
ELECTRON DENSITY
HEATING
INSTABILITY
INSTABILITY GROWTH RATES
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONOSPHERE
IONOSPHERIC STORMS
LORENTZ FORCE
MOLECULE COLLISIONS
PARAMETRIC INSTABILITIES
PLANETARY IONOSPHERES
PLASMA HEATING
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES