@Article{ChakrabartyFeGuPaAbSe:2014:PrAsFl,
author = "Chakrabarty, D. and Fejer, B. G. and Gurubaran, S. and Pant, Tarun
K. and Abdu, Mangalathayil Ali and Sekar, R.",
affiliation = "Physical Research LaboratoryAhmedabad, India and Center for
Atmospheric and Space Sciences, Utah State UniversityLogan, UT,
United States and Indian Institute of GeomagnetismNavi Mumbai,
India and Space Physics Laboratory, Vikram Sarabhai Space
CentreTrivandrum, India and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and Physical Research LaboratoryAhmedabad,
India",
title = "On the pre-midnight ascent of F-layer in the June solstice during
the deep solar minimum in 2008 over the Indian sector",
journal = "Journal of Atmospheric and Solar-Terrestrial Physics",
year = "2014",
volume = "121",
number = "PB",
pages = "177--187",
keywords = "E region, Electric fields, F region, Geomagnetism, Ionosphere,
Solar radiation, Diurnal tides, Equatorial ionosphere, Forecasting
system, Geomagnetic conditions, Solar activity, Tidal winds, Wind
measurement, Zonal electric fields, Solar energy.",
abstract = "Investigations on the variations of the virtual height (h'F) of
the base of the F-layer over Thumba (8.5°N, 77°E, dip lat 0.5°N)
in 2002 (high solar activity) and 2008 (very low solar activity)
under quiet geomagnetic conditions show characteristic
pre-midnight rise of h. '. F in the June solstice of 2008.
Comparison of the h. '. F variations in 2008 over Thumba and
Fortaleza (3.9°S, 38.4°W, dip lat 1.8°S), Brazil, reveals that the
pre-midnight rise of h'F is significantly more over Thumba during
the June solstice. Drift measurements on-board the
Communication/Navigation Outage Forecasting System (C/NOFS)
satellite elicit that the midnight upward drift over the Indian
sector during the northern summer months of 2009 is the largest, a
feature that significantly weakens in 2010. C/NOFS measurements
also confirm the electro-dynamical nature of the pre-midnight h.
'. F rise over the Indian sector in the June solstice during the
low solar activity. As the equatorial F-region vertical drifts
during nighttime are controlled by E-region dynamo driven by tidal
wind system, systematic wind measurements at upper mesospheric
heights by an MF radar (1.98. MHz) from Tirunelveli (8.7°N,
77.8°E, dip lat 0.5°S), India, during 2000-2011 are used to derive
the tidal components. This reveals that the phases of both the
meridional and zonal components of the diurnal tide regress while
the phase of the meridional component of the semidiurnal tide
significantly advances with decreasing solar activity with
concomitant increases in amplitudes during the summer months.
These observations suggest the possible semidiurnal tidal
influence on the pre-midnight h'F rise over the Indian sector in
the June solstice during low solar activity.",
doi = "10.1016/j.jastp.2014.01.002",
url = "http://dx.doi.org/10.1016/j.jastp.2014.01.002",
issn = "1364-6826",
label = "scopus 2015-01 ChakrabartyFeGuPaAbSe:2014:PrAsFl",
language = "en",
urlaccessdate = "28 abr. 2024"
}