Publication Date:
2015-08-21
Description:
We present an empirical model of the high-latitude air density at 450 km, derived from accelerometer measurements by CHAMP and GRACE satellites during 2002–2006, which we call HANDY ( H igh-latitude A tmospheric N eutral D ensit Y ). HANDY consists of a quiet model and disturbance model. The quiet model represents the background thermospheric density for “zero geomagnetic activity” conditions. The disturbance model represents the response of the thermospheric density to solar wind forcing at high latitudes. The solar wind inputs used are the following: (1) solar wind electric field E SW , (2) interplanetary magnetic field (IMF) clock angle C SW , and (3) solar wind dynamic pressure P SW . Both quiet and disturbance models are constructed on the basis of spherical harmonic function fitting to the data. Magnetic coordinates are used for the disturbance model, while geographical coordinates are used for the quiet model. HANDY reproduces main features of the solar wind influence on the high-latitude thermospheric density, such as the IMF B y effect that produces a hemispheric asymmetry in the density distribution.
Print ISSN:
0148-0227
Topics:
Geosciences
,
Physics
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