High-latitude lower thermospheric neutral winds at EISCAT and Sondrestrom during LTCS 1

Journal Article · Fri Feb 01 00:00:00 EST 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JA02314· OSTI ID:5190521

Johnson, R M ^[1]; Virdi, T S ^[2]

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1. Univ. of Michigan, Ann Arbor (USA)
2. Univ. Coll. of Wales, Aberystwyth (England)

The incoherent scatter radar located at Soendre Stroemfjord, Greenland (67{degree}N, 51{degree}W, 74.5{degree}{Lambda}) and the EISCAT incoherent scatter facility located in northern Scandinavia (69.5{degree}N, 19{degree}E, 66.3{degree}{Lambda}) both obtained E and F region measurements during the first campaign of the Lower Thermosphere Coupling Study (LTCS 1, September 21-25, 1987). Neutral winds deduced from these measurements have been analyzed for their mean flow and tidal components. A number of the altitude profiles for the mean winds and the diurnal and semidiurnal wave components at the two radar locations show similar variations with height, indicating that latitudinal rather than longitudinal effects are dominant in determining the observed wind field. Diurnal tidal amplitudes and phases are reasonably well represented by theoretical model results (Forbes, 1982). The semidiurnal amplitudes and phases, although somewhat consistent between the two radars, are not well represented in equinox tidal model results (Forbes and Vial, this issue). Results from both radars indicate a vertical wavelength for the zonal semidiurnal oscillation of approximately 60 km. During a period of impulsive magnetospheric forcing (September 22-23), winds deduced from measurements at both radars show enhanced eastward flows near midnight accompanied by equatorward winds at Sondrestrom. Comparison with the results of a National Center for Atmospheric Research thermosphere-ionosphere general circulation model (TIGCM) simulation of the LTCS 1 interval shows generally better agreement with the observations at EISCAT than at Sondrestrom.

• OSTI ID: 5190521
• Journal Information: Journal of Geophysical Research; (United States), Vol. 96:A2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
THERMOSPHERE
WIND
ALTITUDE
COMPARATIVE EVALUATIONS
DAILY VARIATIONS
DATA ACQUISITION
DATA ANALYSIS
E REGION
EARTH MAGNETOSPHERE
F REGION
GENERAL CIRCULATION MODELS
HEIGHT
LATITUDE EFFECT
MATHEMATICAL MODELS
RADAR
TIDE
DIMENSIONS
EARTH ATMOSPHERE
EVALUATION
GEOGRAPHICAL VARIATIONS
IONOSPHERE
MEASURING INSTRUMENTS
PLANETARY IONOSPHERES
RANGE FINDERS
VARIATIONS
640200* - Atmospheric Physics