Abstract
Abstract. This work presents the daytime behavior of the intermediate
layer (ILs) parameters (the virtual height – h'IL, and the top frequency – ftIL) over
the low-latitude region of Cachoeria Paulista (CP, 22.42∘ S;
45∘ W, I: −34.59∘) during the 2009 deep solar minimum.
Under such a unique condition, this research reveals the ILs' quiet state seasonal
behavior as well as its responses to moderate changes in the geomagnetic
activity. The main results show that even small variations of geomagnetic
activity (quantified by the planetary Kp index) are able to modify the
dynamics of the ILs parameters. For the first time, it was observed that during
the summer, the h'IL decreases rapidly with the increase of geomagnetic
activity, mainly in the early morning hours, while in the following hours, a
smoothed rise of the IL was found in all seasons analyzed. Regarding the
IL frequency, it was observed that after 12:00 LT, there is a tendency to
decrease with the increase of magnetic disturbances, this
characteristic being more intense after 16:00 LT for summer and winter. For the
equinox, such variation was detected, however with half of the amplitude of
the other seasons. In addition, the domain of the annual
periodicity of the ftIL stands out, while the h'IL presents a semiannual component under the
condition of geomagnetic quiet.
Subject
Space and Planetary Science,Earth and Planetary Sciences (miscellaneous),Atmospheric Science,Geology,Astronomy and Astrophysics
Reference47 articles.
1. Abdu, M. A., Jayachandran, P. T., MacDougall, J., Cecile, J. F., and Sobral, J. H. A.: Equatorial F zonal plasma irregularity drifts under magnetospheric disturbances, Geophys. Res. Lett., 25, 4137–4140, https://doi.org/10.1029/1998GL900117, 1998.
2. Aponte, N., Brum, C. G. M., Sulzer, M. P., and Gonzalez, S. A.: Measurements of
the O+ to H+ transition height and ion temperatures in the lower topside
ionosphere over Arecibo for equinox conditions during the 2008–2009 extreme
solar minimum, J. Geophys. Res.-Space, 118, 4465–4470,
https://doi.org/10.1002/jgra.50416, 2013.
3. Balan, N., Chen, C. Y., Liu, J. Y., and Bailey, G. J.: Behaviour of the low
latitude ionosphere-thermosphere system at long deep solar minimum, Ind.
J. Radio Space Phys., 41, 89–97, 2012.
4. Brum, C. G. M.: The impacts of particle precipitation spectrum on the 30 MHz
cosmic noise absorption over the under the South Atlantic Anomaly Region,
2021 34th General Assembly and Scientific Symposium of the International
Union of Radio Science (URSI GASS), Rome, Italy, 28 August–4 September 2021, 1–4, https://doi.org/10.23919/URSIGASS51995.2021.9560414, 2021.
5. Brum, C. G. M., Abdu, M. A., Batista, I. S., Carrasco, A. J., and Santos, P. M. T.:
Numerical Simulation of Nighttime Electron Precipitation in the Lower
Ionosphere over a Sub-Auroral Region, Adv. Space Res., 37,
1051–1057, https://doi.org/10.1016/j.asr.2006.02.003, 2006.
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