Self-consistent modelling of the daytime electron density profile in the ionospheric F region
A theoretical self-consistent method for the description of daytime <i>N<sub>e</sub>(h)</i> profiles in the ionospheric F region measured by EISCAT is proposed. It is based on the use of a theoretical F-region model and measured electron density, <i>N<sub>e<...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
1997-03-01
|
| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/15/314/1997/angeo-15-314-1997.pdf |
| _version_ | 1818049729151369216 |
|---|---|
| author | A. Mikhailov A. Mikhailov K. Schlegel |
| author_facet | A. Mikhailov A. Mikhailov K. Schlegel |
| author_sort | A. Mikhailov |
| collection | DOAJ |
| description | A theoretical self-consistent method for the
description of daytime <i>N<sub>e</sub>(h)</i> profiles in the ionospheric F
region measured by EISCAT is proposed. It is based on the use of a theoretical
F-region model and measured electron density, <i>N<sub>e</sub>(h)</i>,
electron, <i>T<sub>e</sub>(h)</i>, and ion temperature, <i>T<sub>i</sub>(h)</i>,
and field-aligned plasma drift <i>V<sub>l</sub>(h)</i> profiles. The method
describes the observed <i>N<sub>e</sub>(h)</i> profile with high accuracy for
quiet and disturbed conditions. Two versions of the method are considered: in
the first the exospheric temperature <i>T<sub>ex</sub></i> is derived
from a procedure minimizing [log(<i>N<sub>e</sub>(h)</i><sub>obs</sub> / <i>N<sub>e</sub>(h)</i><sub>cal</sub>]<sup>2</sup>, in the second <i>T<sub>ex</sub></i> is deduced from the ion energy
conservation in the F region. The method allows us to infer from the
incoherent-scatter observations: concentrations of atomic oxygen, [O], molecular
oxygen, [O<sub>2</sub>], molecular nitrogen, [N<sub>2</sub>]
the vertical plasma drift, <i>W</i>, the exospheric temperature. <i>T<sub>ex</sub></i>, and the shape parameter <i>S</i> in the neutral
temperature profile. The ratio ([O<sup>+</sup>]/<i>N<sub>e</sub></i>) calculated
by the theoretical model is used to correct <i>T<sub>e</sub>(h), T<sub>i</sub>(h)</i> and N<sub>e</sub>(h)</i>
profiles routinely measured with EISCAT which are known
to depend strongly on the actual applied ion-composition model. Such a
correction is especially important for geomagnetically disturbed periods when
the F region is strongly enriched with molecular ions. We conclude that four of
the six thermospheric parameters, namely [O], [N<sub>2</sub>], <i>W</i> and <i>T<sub>ex</sub></i> can be
confidently inferred from the EISCAT observations, while the other two derived
parameters, [O<sub>2</sub>] ans <i>S</i> are less reliable.
The method can be used for the analysis of long-term (seasonal, solar cycle) as
well as for day-to-day variations of the thermospheric parameters and the
F-region ion composition using daytime incoherent-scatter observations. |
| first_indexed | 2024-12-10T10:42:12Z |
| format | Article |
| id | doaj.art-bfd77388b3bf408eacef08cb48331315 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-12-10T10:42:12Z |
| publishDate | 1997-03-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-bfd77388b3bf408eacef08cb483313152022-12-22T01:52:16ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05761997-03-011531432610.1007/s00585-997-0314-9Self-consistent modelling of the daytime electron density profile in the ionospheric F regionA. Mikhailov0A. Mikhailov1K. Schlegel2<i>Permanent address:</i> Institute for Applied Geophysics, 129128 Rostokinskaya 9, Moscow, RussiaMax-Planck-Institut für Aeronomie, Postfach 20, D-37189 Katlenburg-Lindau, GermanyMax-Planck-Institut für Aeronomie, Postfach 20, D-37189 Katlenburg-Lindau, GermanyA theoretical self-consistent method for the description of daytime <i>N<sub>e</sub>(h)</i> profiles in the ionospheric F region measured by EISCAT is proposed. It is based on the use of a theoretical F-region model and measured electron density, <i>N<sub>e</sub>(h)</i>, electron, <i>T<sub>e</sub>(h)</i>, and ion temperature, <i>T<sub>i</sub>(h)</i>, and field-aligned plasma drift <i>V<sub>l</sub>(h)</i> profiles. The method describes the observed <i>N<sub>e</sub>(h)</i> profile with high accuracy for quiet and disturbed conditions. Two versions of the method are considered: in the first the exospheric temperature <i>T<sub>ex</sub></i> is derived from a procedure minimizing [log(<i>N<sub>e</sub>(h)</i><sub>obs</sub> / <i>N<sub>e</sub>(h)</i><sub>cal</sub>]<sup>2</sup>, in the second <i>T<sub>ex</sub></i> is deduced from the ion energy conservation in the F region. The method allows us to infer from the incoherent-scatter observations: concentrations of atomic oxygen, [O], molecular oxygen, [O<sub>2</sub>], molecular nitrogen, [N<sub>2</sub>] the vertical plasma drift, <i>W</i>, the exospheric temperature. <i>T<sub>ex</sub></i>, and the shape parameter <i>S</i> in the neutral temperature profile. The ratio ([O<sup>+</sup>]/<i>N<sub>e</sub></i>) calculated by the theoretical model is used to correct <i>T<sub>e</sub>(h), T<sub>i</sub>(h)</i> and N<sub>e</sub>(h)</i> profiles routinely measured with EISCAT which are known to depend strongly on the actual applied ion-composition model. Such a correction is especially important for geomagnetically disturbed periods when the F region is strongly enriched with molecular ions. We conclude that four of the six thermospheric parameters, namely [O], [N<sub>2</sub>], <i>W</i> and <i>T<sub>ex</sub></i> can be confidently inferred from the EISCAT observations, while the other two derived parameters, [O<sub>2</sub>] ans <i>S</i> are less reliable. The method can be used for the analysis of long-term (seasonal, solar cycle) as well as for day-to-day variations of the thermospheric parameters and the F-region ion composition using daytime incoherent-scatter observations.https://www.ann-geophys.net/15/314/1997/angeo-15-314-1997.pdf |
| spellingShingle | A. Mikhailov A. Mikhailov K. Schlegel Self-consistent modelling of the daytime electron density profile in the ionospheric F region Annales Geophysicae |
| title | Self-consistent modelling of the daytime electron density profile in the ionospheric F region |
| title_full | Self-consistent modelling of the daytime electron density profile in the ionospheric F region |
| title_fullStr | Self-consistent modelling of the daytime electron density profile in the ionospheric F region |
| title_full_unstemmed | Self-consistent modelling of the daytime electron density profile in the ionospheric F region |
| title_short | Self-consistent modelling of the daytime electron density profile in the ionospheric F region |
| title_sort | self consistent modelling of the daytime electron density profile in the ionospheric f region |
| url | https://www.ann-geophys.net/15/314/1997/angeo-15-314-1997.pdf |
| work_keys_str_mv | AT amikhailov selfconsistentmodellingofthedaytimeelectrondensityprofileintheionosphericfregion AT amikhailov selfconsistentmodellingofthedaytimeelectrondensityprofileintheionosphericfregion AT kschlegel selfconsistentmodellingofthedaytimeelectrondensityprofileintheionosphericfregion |