Goose Bay radar observations of earth-reflected atmospheric gravity waves in the high-latitude ionosphere

Technical Report · Thu May 03 00:00:00 EDT 1990

OSTI ID:6137826

Ruohoniemi, J M; Greenwald, R A; Baker, K B; Samson, J C

An HF backscatter radar at Goose Bay, Labrador made it possible to observe irregularities in the distribution of ionospheric ionization at E and F region altitudes (100 - 600 km) in the high-latitude (65 - 85 deg Lambda) ionosphere. Recently it has been established that the passage of atmospheric gravity waves perturbs the ionosphere in ways that are readily detected in returns that reflect off the ionospheric layers. The particular strength of the technique lies in the nearly instantaneous measurement of gravity wave effects over large areas ( 1 million sq. km). With this information the propagation of gravity waves can be accurately modelled. Generally gravity waves are observed during daylight hours propagating away from the auroral electrojets. The propagation mode involves penetration of wave energy through the lower atmosphere and subsequent reflection by the earth's surface. The frequencies associated with the waves lie in the 0.4 - 0.6 mHz range and the wavelengths vary from 300 to 500 km. The excitation sources appear to lie in the vicinity of the high-latitude electrojets. In this paper we outline the analysis of gravity wave effects on HF propagation and present an example of a modelled gravity wave event.

• Research Organization: Johns Hopkins Univ., Laurel, MD (United States). Applied Physics Lab.
• OSTI ID: 6137826
• Report Number(s): AD-P-006275/2/XAB
• Resource Relation: Other Information: This article is from 'The Effect of the Ionosphere on Radiowave Signals and Systems Performance Based on Ionospheric Effects Symposium Held on 1-3 May 1990', AD-A233 797, p100-107. Prepared in cooperation with University of Alberta, Department of Physics, Canada
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
GRAVITY WAVES
WAVE PROPAGATION
IONOSPHERE
AURORAE
BACKSCATTERING
DAILY VARIATIONS
DISTURBANCES
E REGION
ELECTROJETS
F REGION
RADAR
REFLECTION
CURRENTS
EARTH ATMOSPHERE
ELECTRIC CURRENTS
MEASURING INSTRUMENTS
PLANETARY IONOSPHERES
RANGE FINDERS
SCATTERING
VARIATIONS
661320* - Auroral
Ionospheric
& Magnetospheric Phenomena- (1992-)