GPS Solutions

, 14:75

Electron density profiles in the equatorial ionosphere observed by the FORMOSAT-3/COSMIC and a digisonde at Jicamarca

  • Jann-Yenq Liu
  • Chien-Chih Lee
  • Jhih-Yung Yang
  • Chao-Yen Chen
  • Bodo W. Reinisch
Original Article

Abstract

We examine for the first time the ionospheric electron density profiles concurrently observed by the GPS occultation experiment (GOX) onboard the FORMOSAT-3/COSMIC (F3/C) and the ground-based digisonde portable sounder DPS-4 at Jicamarca (12°S, 283°W, 1°N geomagnetic) in 2007. Our results show that the F3/C generally underestimates the F2-peak electron density NmF2 and the F2-peak height hmF2. On the other hand, when the equatorial ionization anomaly (EIA) pronouncedly appears during daytime, the total electron content (TEC) derived from the radio occultation of the GPS signal recorded by the F3/C GOX is significantly enhanced. This results in the NmF2 at Jicamarca being overestimated by the Abel inversion on the enhanced TEC during the afternoon period.

Keywords

FORMOSAT-3/COSMIC Digisonde NmF2 hmF2 Equatorial ionization anomaly 

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Jann-Yenq Liu
    • 1
    • 2
  • Chien-Chih Lee
    • 3
  • Jhih-Yung Yang
    • 1
  • Chao-Yen Chen
    • 1
  • Bodo W. Reinisch
    • 4
  1. 1.Institute of Space ScienceNational Central UniversityJhongliTaiwan
  2. 2.Center for Space and Remote Sensing ResearchNational Central UniversityJhongliTaiwan
  3. 3.General Education CenterChing-Yun UniversityJhongliTaiwan
  4. 4.Center for Atmospheric ResearchUniversity of MassachusettsLowellUSA

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