Numerical Studies of Seasonal and Latitudinal Variability in a Model Thermosphere

The diurnal heat budget of the thermosphere

“…In solving the energy balance equation for the thermospheric region, it has been customary to represent the heat input term by multiplying the absorbed solar ultraviolet energy with a constant factor, often referred to as a heating efficiency [Harris and Priester, 1962;Lagos and Mahoney, 1967;Chandra and Stubbe, 1970;Izakov, 1971]. Though the estimate of the heating efficiency varied over a wide range, from 0.1-0.6 [Nicolet (1961), Hanson and Johnson (1961), Hunt and Van Zandt (1961), Lazarev (1963)] and the various authors used values most suited to them, the concept of heating efficiency was useful in providing a short-cut alternative to a laborious calculation of multiple-channel energy and radiative transfer problem.…”

Venus: An Upper Limit on Intrinsic Magnetic Dipole Moment Based on Absence of a Radiation Belt

“…There are also inconsistencies between such radar measure ments and temperatures deduced from Langmuir probes [Carlson and Sayers, 1970]. Nevertheless temperatures maximizing later in the afternoon are more consistent with some theoretical models [Lagos and Mahoney 1967]. If indeed a phase difference exists between the maximum of temperature and density, it may result from longitudinal circulation and adiabatic heating [Blum et al, 1970], but the circulation would be significantly constrained by ion drag.…”

“…A number of theoretical models have recently btei developed that consider the diurnal variation of density and temperature in the thermosphere and exospherc [Chandra and Stubbe, 1970;Dickinson et al, l%g ;Friedman, 1967;Hodges and Johnson, 1968;Lagos 1967;Lagos and Mahoney, 1967;Volland, 1969a, b, c: Volland et al, 1968Volland and Mayr, 1969]. These models plus the latest three-dimensional global models of Friedman, of Harris, and of Volland and Mayr have recently been critically reviewed [Blum et al, 1970], Ultimately the three-dimensional theoretical models need to take into account the newly discovered latitudi nal-seasonal variations.…”

Wave motions in the atmosphere and related ionospheric phenomena

“…We should also notice a remarkable change in the magnitude and direction of the ionospheric drift (90-100 km range) during anomaly periods (Lauter, 1967;Lauter and Sprenger, 1968;Sprenger and Lysenko, 1972) and also of the drift of meteor trails (Hooke, 1972). Maeda, K. (1971) also discussed the wind effect on electron density distribution, i.e.…”

“…Adding this source to the solar EUV heat input they could fit the satellite drag observations. Lagos and Mahoney (1967) showed that horizontal energy transport or another heating mechanism must be important for the heat balance of the thermosphere. indicated in their model that the time of the diurnal density maximum shifted toward the early afternoon as the result of adiabatic heating due to vertical motions.…”