High-frequency radar observations of atmospheric gravity waves in the high-latitude ionosphere

Journal Article · Tue Aug 01 04:00:00 EDT 1989 · Geophysical Research Letters (American Geophysical Union); (USA)

DOI:https://doi.org/10.1029/GL016i008p00875· OSTI ID:5837316

Samson, J C ^[1]; Greenwald, R A; Ruohoniemi, J M; Baker, K B ^[2]

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1. Univ. of Alberta, Edmonton (Canada)
2. Johns Hopkins Univ., Laurel, MD (USA)

The Johns Hopkins University high-frequency coherent scatter radar at Goose Bay, Labrador, often observes the effects of propagating atmospheric gravity waves, particularly in ground backscatter returns. To date, these waves have been identified in late fall and early winter on propagation paths directed over the Davis Strait, between northeastern Canada and Greenland. The waves appear as spatially localized enhancements in the backscattered powers, Doppler velocities, and reflection heights. They are generally observed during daylight hours and are usually accompanied by backscatter from higher-latitude ionospheric irregularities that appear to be located near the ionospheric convections reversal boundary. The lowest frequencies associated with the gravity waves lie in the range 0.4 to 0.6 mHz, and the wavelengths lie in the range 300 to 600 km. The waves generally propagate equatorward at an angle of 150{degree} to 180{degree} east of geographic north. During intervals with an expanded polar cap, northward propagating gravity waves are sometimes observed. Measurements of the parameters of the waves and the ranges to the sources suggest that the waves are excited at a height of 100 to 150 km near the convection reversal boundary and the polar cusp, and that the bulk of the observed perturbations are due to Earth-reflected waves.

• OSTI ID: 5837316
• Journal Information: Geophysical Research Letters (American Geophysical Union); (USA), Journal Name: Geophysical Research Letters (American Geophysical Union); (USA) Vol. 16:8; ISSN GPRLA; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BACKSCATTERING
CALCULATION METHODS
CANADA
CONVECTION
DISTURBANCES
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRON DENSITY
ENERGY TRANSFER
GRAVITY WAVES
GREENLAND
HEAT TRANSFER
IONOSPHERE
IONOSPHERIC STORMS
MASS TRANSFER
MEASURING INSTRUMENTS
NORTH AMERICA
PLANETARY IONOSPHERES
POLAR CUSP
POLAR REGIONS
RADAR
RANGE FINDERS
REFLECTION
SCATTERING
THERMOSPHERE
TRAVELLING IONOSPHERIC DISTURBANCE
WAVE PROPAGATION