Advanced search
Start date
Betweenand
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Solar flux effects on the equatorial evening vertical drift and meridional winds over Brazil: A comparison between observational data and the IRI model and the HWM representations

Full text
Author(s):
Abdu, M. A. [1] ; Batista, I. S. [1] ; Brum, C. G. M. [2] ; MacDougall, J. W. [3] ; Santos, A. M. [1] ; de Souza, J. R. [1] ; Sobral, J. H. A. [1]
Total Authors: 7
Affiliation:
[1] INPE, BR-12201970 Sao Paulo - Brazil
[2] Natl Astron & Ionosphere Ctr, Space & Atmospher Sci Dept, Arecibo Observ Atmospher Sci, Arecibo, PR 00612 - USA
[3] Univ Western Ontario, Dept Elect Engn, London, ON N6A 5B9 - Canada
Total Affiliations: 3
Document type: Journal article
Source: Advances in Space Research; v. 46, n. 8, p. 1078-1085, OCT 15 2010.
Web of Science Citations: 13
Abstract

We present the results of a study of the equatorial evening F region prereversal vertical drift enhancement over Brazil as a function of solar flux (F10.7). The vertical drift is measured from true heights obtained from digisondes operated at an equatorial site, Sao Luis, and at an off equatorial site, Fortaleza. The different magnetic inclinations of the two sites cause different degree of dependence of the vertical drift on magnetic meridional winds permitting an evaluation of the solar flux control on both the evening vertical drift (zonal electric field) and meridional winds. The analysis period covers the year 2001 and 2004 during which the monthly mean F10.7 varied from 245 to 80. The solar flux dependence of the vertical drift of the evening F layer as obtained from the data are compared with the representation of such dependence in the IRI model. While the IRI description of such dependence appears comparable to that is determined from observational data there is significant difference between the drift values in the two cases, the IRI representation being an underestimation of the observed drift for all flux values. The results are discussed from the perspective of validating the IRI model representations of the vertical drift. The results of the study also shows that the HWM description of the evening thermospheric meridional wind in the Brazilian sector, shows agreement with observation for lower F10.7 values, while it significantly deviates from the observed/calculated meridional wind for higher solar flux values. (C) 2010 Published by Elsevier Ltd. on behalf of COSPAR. (AU)

FAPESP's process: 99/00437-0 - Studies of the interactive processes of the equatorial ionosphere-thermosphere system
Grantee:Mangalathayil Ali Abdu
Support type: Research Projects - Thematic Grants