Extreme Longitudinal Variability of Plasma Structuring in the Equatorial Ionosphere on a Magnetically Quiet Equinoctial Day

Authors

Sarah E. McDonald, Naval Research Laboratory
Sunanda Basu, Boston University
Santimay Basu, Air Force Research Laboratory
Keith M. Groves, Air Force Research Laboratory
Cesar E. Valladares, Utah State University
Ludger Scherliess, Utah State UniversityFollow
Donald C. Thompson, Utah State UniversityFollow
Robert W. Schunk, Utah State UniversityFollow
Jan Josef Sojka, Utah State UniversityFollow

Document Type

Article

Journal/Book Title/Conference

Radio Science

Volume

41

Issue

RS6S24

Publisher

American Geophysical Union

Publication Date

2006

Abstract

We investigate the extreme longitudinal variability of equatorial scintillation under quiet magnetic conditions during 22–23 March 2002. Scintillation Network Decision Aid (SCINDA) observations show intense activity in the South American–Atlantic sector during local evening hours, whereas an absence of scintillation is seen in the far east Asian sector. Ground- and space-based measurements from SCINDA, the Global Ultraviolet Imager (GUVI), TOPEX, and a chain of GPS receivers are used in combination with the Utah State University Global Assimilation of Ionospheric Measurements (USU-GAIM) model to explore the relationship between the large-scale ionization distribution and small-scale irregularities at low latitudes in both the scintillating and nonscintillating longitude sectors. Our analysis shows that there are significant differences in the evolution of the ionization distributions during the evening hours, which are likely the result of differences in the daytime and postsunset vertical plasma drift in the two sectors. This study demonstrates the importance of USU-GAIM as a new tool for investigating longitudinal as well as day-to-day variability that is observed in the large-scale distribution of the ionosphere and how this relates to the occurrence of scintillation.

Comments

Originally published by the American Geophysical Union in Radio Science.

Recommended Citation

McDonald, S. E., S. Basu, S. Basu, K. M. Groves, C. E. Valladares, L. Scherliess, D. C. Thompson, R. W. Schunk, J. J. Sojka, and L. Zhu (2006), Extreme longitudinal variability of plasma structuring in the equatorial ionosphere on a magnetically quiet equinoctial day, Radio Sci., 41, RS6S24, doi:10.1029/2005RS003366.