Mid- and low-latitude prompt-penetration ionospheric zonal plasma drifts

1998 ◽  
Vol 25 (16) ◽  
pp. 3071-3074 ◽  
Author(s):  
Bela G. Fejer ◽  
Ludger Scherliess
Keyword(s):  
Low Latitude ◽  
Plasma Drifts

scholarly journals Lunar atmospheric tidal effects in the plasma drifts observed by the Low-Latitude Ionospheric Sensor Network

2011 ◽  
Vol 116 (A7) ◽  
pp. n/a-n/a ◽  
Author(s):  
Vince Eccles ◽  
Donald D. Rice ◽  
Jan J. Sojka ◽  
Cesar E. Valladares ◽  
Terence Bullett ◽  
...  
Keyword(s):  
Sensor Network ◽  
Tidal Effects ◽  
Low Latitude ◽  
Plasma Drifts

scholarly journals LION: A dynamic computer model for the low-latitude ionosphere

2007 ◽  
Vol 25 (11) ◽  
pp. 2371-2392 ◽  
Author(s):  
J. A. Bittencourt ◽  
V. G. Pillat ◽  
P. R. Fagundes ◽  
Y. Sahai ◽  
A. A. Pimenta
Keyword(s):  
Magnetic Field ◽  
Time Evolution ◽  
Computer Model ◽  
Transport Processes ◽  
Time Dependent ◽  
Low Latitude ◽  
Radiation Chemical ◽  
Neutral Winds ◽  
Plasma Drifts ◽  
Low Latitude Ionosphere

Abstract. A realistic fully time-dependent computer model, denominated LION (Low-latitude Ionospheric) model, that simulates the dynamic behavior of the low-latitude ionosphere is presented. The time evolution and spatial distribution of the ionospheric particle densities and velocities are computed by numerically solving the time-dependent, coupled, nonlinear system of continuity and momentum equations for the ions O+, O2+, NO+, N2+ and N+, taking into account photoionization of the atmospheric species by the solar extreme ultraviolet radiation, chemical and ionic production and loss reactions, and plasma transport processes, including the ionospheric effects of thermospheric neutral winds, plasma diffusion and electromagnetic E×B plasma drifts. The Earth's magnetic field is represented by a tilted centered magnetic dipole. This set of coupled nonlinear equations is solved along a given magnetic field line in a Lagrangian frame of reference moving vertically, in the magnetic meridian plane, with the electromagnetic E×B plasma drift velocity. The spatial and time distribution of the thermospheric neutral wind velocities and the pattern of the electromagnetic drifts are taken as known quantities, given through specified analytical or empirical models. The model simulation results are presented in the form of computer-generated color maps and reproduce the typical ionization distribution and time evolution normally observed in the low-latitude ionosphere, including details of the equatorial Appleton anomaly dynamics. The specific effects on the ionosphere due to changes in the thermospheric neutral winds and the electromagnetic plasma drifts can be investigated using different wind and drift models, including the important longitudinal effects associated with magnetic declination dependence and latitudinal separation between geographic and geomagnetic equators. The model runs in a normal personal computer (PC) and generates color maps illustrating the typical behavior of the low-latitude ionosphere for a given longitudinal region, for different seasons, geophysical conditions and solar activity, at each instant of time, showing the time evolution of the low-latitude ionosphere, between about 20° north and south of the magnetic equator. This paper presents a detailed description of the mathematical model and illustrative computer results.

scholarly journals Longitudinal dependence of middle and low latitude zonal plasma drifts measured by DE-2

2007 ◽  
Vol 25 (12) ◽  
pp. 2551-2559 ◽  
Author(s):  
J. W. Jensen ◽  
B. G. Fejer
Keyword(s):  
Middle Latitude ◽  
Early Morning ◽  
Quiet Time ◽  
Low Latitude ◽  
Late Night ◽  
Middle Latitudes ◽  
Plasma Drifts ◽  
Longitudinal Variations ◽  
December Solstice ◽  
European Sector

Abstract. We used ion drift observations from the DE-2 satellite to study for the first time the longitudinal variations of middle and low latitude F region zonal plasma drifts during quiet and disturbed conditions. The quiet-time middle latitude drifts are predominantly westward; the low latitude drifts are westward during the day and eastward at night. The daytime quiet-time drifts do not change much with longitude; the nighttime drifts have strong season dependent longitudinal variations. In the dusk-premidnight period, the equinoctial middle latitude westward drifts are smallest in the European sector and the low latitude eastward drifts are largest in the American-Pacific sector. The longitudinal variations of the late night-early morning drifts during June and December solstice are anti-correlated. During geomagnetically active times, there are large westward perturbation drifts in the late afternoon-early night sector at upper middle latitudes, and in the midnight sector at low latitudes. The largest westward disturbed drifts during equinox occur in European sector, and the smallest in the Pacific region. These results suggest that during equinox SAPS events occur most often at European longitudes. The low latitude perturbation drifts do not show significant longitudinal

Low-latitude plasma drifts from a simulation of the global atmospheric dynamo

1993 ◽  
Vol 98 (A4) ◽  
pp. 6039-6046 ◽  
Author(s):  
D. J. Crain ◽  
R. A. Heelis ◽  
G. J. Bailey ◽  
A. D. Richmond
Keyword(s):  
Low Latitude ◽  
Plasma Drifts

The electrodynamic influence of thermospheric winds in the daytime ionosphere.

2021 ◽  
Author(s):  
Thomas Immel ◽  
Brian Harding ◽  
Roderick Heelis ◽  
Astrid Maute ◽  
Jeffrey Forbes ◽  
...  
Keyword(s):  
Time Frame ◽  
Plasma Velocity ◽  
State Variables ◽  
Altitude Range ◽  
Low Latitude ◽  
Plasma Drifts ◽  
Wind Measurements ◽  
Thermospheric Winds ◽  
Low Latitude Ionosphere ◽  
Measurement Capabilities

<p>The electrodynamic influence of thermospheric winds is an effect thought to dominate the development of<span> </span>the daytime low-latitude ionosphere, through the generation of dynamo currents and associated vertical plasma drifts. Until recently, observations of the thermospheric and ionopsheric state variables have mainly been defined and compared on climatological time scales, due to their collection from separate observatories with disparate measurement capabilities.<span>  </span>These datasets are inadequate for investigation of the actual action of thermospheric drivers as they modify the ionospheric state, as the response clearly changes on 24-hour timescales, and shorter when viewed in the a constant-local-time frame<span> </span>of reference. New observatiions of thermospheric winds, uninterrupted over the 90-300 km altitude range, are now provided by the Ionospheric Connection Explorer along with simultaneous plasma velocity and density measurments. These observations are directly comparable to the wind measurements in crossings of the magnetic equator, where the winds are magnetically conjugate to the drift measurements. Investigation of the noon-sector drifts vs wind drivers is presented. We find that the local driver is clearly evident in the noon-time vertical plasma drifts under all conditions.</p><p> </p>

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