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This content will become publicly available on August 13, 2026

Title: Mass Density and Wind Perturbations in the High‐Latitude Thermosphere
Abstract This work investigates mesoscale structures in the northern high‐latitude thermosphere using an ascending‐descending accelerometry (ADA) technique to determine whether observed in‐track acceleration perturbations are influenced by in‐track winds. The ADA technique is applied to accelerometer measurements from the Challenging Minisatellite Payload mission between 2003 and 2006 during quiet geomagnetic activity, revealing a climatological view of regularly occurring acceleration perturbation structures. The ADA technique reveals a structured acceleration enhancement on the dayside with a strong signature of density dominance confined to a spatial envelope ranging from 8:00 to 17:00 magnetic local time (MLT) and between 72° and 82° magnetic latitude, aligning with past observations of the cusp density enhancement. Additionally, this sector displays a wind perturbation structure with a reversal in direction that coincides with the center of the enhancement. The premidnight quadrant shows strong evidence of wind influence in the acceleration perturbations from 18:00 to 24:00 MLT between 70° and 90° magnetic latitude associated with southward wind perturbations. This suggests that past analyses of this region could have misidentified this structure as a density enhancement by neglecting in‐track wind influences in accelerometry‐derived mass density data sets. The early morning quadrant consists of negative acceleration perturbations attributed to density depletions, with signatures of southward wind perturbations. These mass density perturbations, in conjunction with in‐track wind perturbations, suggest that the coupled ionosphere‐thermosphere mechanisms responsible for the high‐latitude density structure also influence the wind structure. This work is supplemented with TIEGCM simulations to verify the accuracy of ADA and highlight discrepancies between the simulations and observations.  more » « less
Award ID(s):
2028032
PAR ID:
10646746
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Journal of Geophysical Research: Space Physics
Volume:
130
Issue:
8
ISSN:
2169-9380
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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