@Article{PaulaKSTSGMLKKT:2002:IoIrZo,
author = "Paula, Eurico Rodrigues de and Kantor, Ivan Jelinek and Sobral,
Jos{\'e} Humberto Andrade and Takahashi, Hisao and Santana,
Daniela Cristina and Gobbi, Delano and Medeiros, Amauri Fragoso de
and Limiro, L. A. T. and Kil, H. and Kintner, P. M. and Taylor,
Michael J.",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais
(INPE)} and {Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and Johns Hopkins APL,
Laurel, MD, USA and Cornell University, Ithaca, NY, USA and Utah
State University, Logan, UT, USA",
title = "Ionospheric irregularity zonal velocities over Cachoeira
Paulista",
journal = "Journal of Atmospheric and Solar-Terrestrial Physics",
year = "2002",
volume = "64",
number = "12-14",
pages = "1511--1616",
month = "Aug.-Sep.",
keywords = "aeronomia, global positioning system, equatorial spread-f, radar
observations, drifts, scintillation, Brazil, disturbances.",
abstract = "We have studied the zonal drift velocity of nighttime ionospheric
irregularities from Cachoeira Paulista (22.41°S, 45°W, dip
latitude - 17.43°), a station under the Equatorial Anomaly, from
December 1998 to February 1999 using LI band GPS receivers and OI
630 nm all-sky images. The average decimetric solar flux index for
this period of increasing solar activity was about 145 and
magnetically quiet days with SigmaKp < 24 were selected. The GPS
technique used receivers spaced 55 in in the magnetic east-west
direction and probed small scale plasma structures (scale size
about 400 m) at altitudes near 350 kill. The zonal irregularity
drift velocities measured by this technique were eastward with
values of about 160 m/s at 20 LT, about 140 m/s around midnight,
and decreased further in the post-midnight sector. The variability
of these drifts decreased significantly after midnight. The zonal
velocities of large scale plasma structure were obtained using
01630 nm all-sky images from a region located about 24.1°S and
45°W at a nominal height of 250 kin which corresponds to the
bubble projection along the magnetic field lines to 350 km over
Cachoeira Paulista. These all-sky imager derived zonal drifts are
also eastward, but have magnitudes smaller than the spaced GPS
eastward drifts, particularly in the pre-midnight sector. We will
discuss these two drift measurement techniques and the
interpretation of our results.",
issn = "1364-6826",
label = "10474",
language = "en",
targetfile = "1-s2.0-S1364682602000883-main.pdf",
urlaccessdate = "2025, Feb. 09"
}