Accession Number:

AD0711782

Title:

TIDAL WINDS IN THE LOWER IONOSPHERE,

Descriptive Note:

Corporate Author:

RAND CORP SANTA MONICA CALIF

Personal Author(s):

• Batten,E. S.

Report Date:

1970-08-01

Pagination or Media Count:

17.0

Abstract:

Many ionospheric phenomena are coupled to the neutral air motions. In particular, tidal motions in the E-region are considered to be the source of the solar daily variation Sq of the geomagnetic field. Moreover, the electric fields produced by the tidal motions may affect the morphology of the F-layer. Thus a description of the tidal winds in the E-region is desirable. However, observations of winds, primarily from meteor-trail and vapor-trail drifts, are available at only a few locations and, in the case of vapor trails, only during the night hours. Further, the interpretation of these observations have produced an inconsistent description of the tides. Therefore, to improve the description of neutral air motions in the E-layer, tidal winds have been computed from theory. To do this, the effects of dissipation and thermal excitation in the thermosphere are considered. Possible forms of dissipation are molecular heat conduction and viscosity, turbulence, and ion drag. Thermospheric excitation may be due to heating by absorption of solar radiation, particle precipitation, and dissipative mechanisms. In this paper, the effects of heat conductivity and the absorption of solar radiation in the thermosphere are added to the existing tidal theory. Author

Descriptors:

• (*IONOSPHERE
• WIND)
• (*GEOMAGNETISM
• DIURNAL VARIATIONS)
• SOLAR RADIATION
• HEATING
• WATER VAPOR
• OZONE
• THERMAL CONDUCTIVITY
• PARTICLE TRAJECTORIES

Subject Categories:

• Atmospheric Physics
• Geomagnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE