Premium
Thermospheric atomic oxygen density estimates using the EISCAT Svalbard Radar
Author(s) -
Vickers H.,
Kosch M. J.,
Sutton E.,
Ogawa Y.,
La Hoz C.
Publication year - 2013
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
eISSN - 2169-9402
pISSN - 2169-9380
DOI - 10.1002/jgra.50169
Subject(s) - thermosphere , incoherent scatter , earth's magnetic field , altitude (triangle) , ionosphere , physics , atmospheric sciences , atmosphere (unit) , quiet , polar , computational physics , f region , environmental science , geophysics , geodesy , geology , magnetic field , meteorology , astronomy , quantum mechanics , geometry , mathematics
Coupling between the ionized and neutral atmosphere through particle collisions allows an indirect study of the neutral atmosphere through measurements of ionospheric plasma parameters. We estimate the neutral density of the upper thermosphere above ~250 km with the European Incoherent Scatter Svalbard Radar (ESR) using the year‐long operations of the International Polar Year from March 2007 to February 2008. The simplified momentum equation for atomic oxygen ions is used for field‐aligned motion in the steady state, taking into account the opposing forces of plasma pressure gradients and gravity only. This restricts the technique to quiet geomagnetic periods, which applies to most of the International Polar Year during the recent very quiet solar minimum. The method works best in the height range ~300–400 km where our assumptions are satisfied. Differences between Mass Spectrometer and Incoherent Scatter and ESR estimates are found to vary with altitude, season, and magnetic disturbance, with the largest discrepancies during the winter months. A total of 9 out of 10 in situ passes by the CHAMP satellite above Svalbard at 350 km altitude agree with the ESR neutral density estimates to within the error bars of the measurements during quiet geomagnetic periods.