Diurnal and Seasonal Variations of Equivalent Slab thickness over Low and Mid Latitude Regions
The equivalent slab-thickness is very important in the study of the complex dynamics of the ionosphere as a result of its ability to determine the skewness of the ionospheric electron density profile. This study involves the day to day and monthly variations of . Ionosonde (FoF2) and Total electron content (TEC) data at the low latitude station of Sao Luis (Glat 2.60° S, Glong 315.80° E and Mlat 6.05° N and Mlong 28.40° E), Brazil and mid latitude station of Chilton (Glat 51.50° N, Glong 359.40° E and Mlat 53.35° N and Mlong 84.34° E), United Kingdom from January 2013 to December 2015 were used in the study of . For Sao Luis station, the diurnal pattern for the different days are characterized by day time (08:00 – 16:00 UT) high values and nighttime (20:00 – 04:00 UT) low values; however, Chilton shows signatures, such as day time low values and nighttime high values. Also, the daytime values (~600 km) of for the low latitude station (Sao Luis) is more than double the mid latitude station (Chilton) maximum value (~235 km) over the years considered. The monthly variation of also indicate a seasonal variation with highest daytime values (400 km) during winter months and lowest (below 300 km) during summer months for the low latitude station (Sao Luis). However, the nighttime values are of the same order (about 200 km) for the low latitude station (Sao Luis). Also, highest daytime values (above 250 km) are observed during summer months and the nighttime values are below 200 km over the years for the mid latitude station (Chilton).
J. E. Titheridge, “The slab thickness of the mid-latitude ionosphere,” Planet. Space Sci., vol. 21, no. 10, pp. 1775–1793, 1973.
D. R. Furman and S. S. Prasad, “Ionospheric slab thickness: Its relation to temperature and dynamics,” J. Geophys. Res., vol. 78, no. 25, pp. 5837–5843, 1973.
R. G. Rastogi, F. A. Sc, K. N. Iyer, and R. P. Sharma, “Ionospheric total electron content and slab-thickness at low latitudes in Indian zone,” vol. 85, no. 6, pp. 415–428, 1977.
A. M. Breed, G. L. Goodwin, A. M. Vandenberg, E. A. Essex, K. J. W. Lynn, and J. H. Silby, “Ionospheric total electron content and slab thickness determined in Australia,” Radio Sci., vol. 32, no. 4, pp. 1635–1643, 1997.
V. K. Pandey, N. K. Sethi, and K. K. Mahajan, “Equivalent slab thickness and its variability: a study with incoherent scatter measurements,” Adv. Sp. Res., vol. 27, no. 1, pp. 60–64, 2001.
B. Jayachandran, T. N. Krishnankutty, and T. L. Gulyaeva, “Climatology of ionospheric slab thickness,” Ann. Geophys., vol. 22, no. 1, pp. 25–33, 2004.
S. Jin, J. H. Cho, and J. U. Park, “Ionospheric slab thickness and its seasonal variations observed by GPS,” J. Atmos. Solar-Terrestrial Phys., vol. 69, no. 15, pp. 1864–1870, 2007.
K. Venkatesh, P. V. S. R. Rao, D. S. V. V. D. Prasad, K. Niranjan, and P. L. Saranya, “Study of TEC, slab-thickness and neutral temperature of the thermosphere in the Indian low latitude sector,” Ann. Geophys., vol. 29, no. 9, pp. 1635–1645, 2011.
B. Muslim, H. Haralambous, C. Oikonomou, and S. Anggarani, “Evaluation of a global model of ionospheric slab thickness for foF2 estimation during geomagnetic storm,” Ann. Geophys., vol. 58, no. 5, 2015.
K. Venkatesh, P. V. S. Rama Rao, D. S. V. V. D. Prasad, K. Niranjan, and P. L. Saranya, “Study of TEC, slab-thickness and neutral temperature of the thermosphere in the Indian low latitude sector,” Ann. Geophys, vol. 29, pp. 1635–1645, 2011.
Z. Huang and H. Yuan, “Climatology of the ionospheric slab thickness along the longitude of 120 E in China and its adjacent region during the solar minimum years of 2007–2009,” Ann. Geophys, vol. 33, pp. 1311–1319, 2015.
L. Liu, M. He, W. Wan, and M. L. Zhang, “Topside ionospheric scale heights retrieved from Constellation Observing System for Meteorology, Ionosphere, and Climate radio occultation measurements,” J. Geophys. Res. Sp. Phys., vol. 113, no. 10, pp. 1–12, 2008.
Liu, L., Huang, H., Chen, Y., Le, H., Ning, B., Wan, W., & Zhang, H., “Deriving the effective scale height in the topside ionosphere based on ionosonde and satellite in situ observations,” J. Geophys. Res. Sp. Phys., vol. 119, no. 10, pp. 8472–8482, 2014.
S. Tulasi Ram, S. Y. Su, C. H. Liu, B. W. Reinisch, and L. A. McKinnell, “Topside ionospheric effective scale heights (HT) derived with ROCSAT-1 and ground-based ionosonde observations at equatorial and midlatitude stations,” J. Geophys. Res. Sp. Phys., vol. 114, no. 10, pp. 1–13, 2009.
M. Henrique, D. Silva, M. Tadeu, and D. A. Honorato, “Study of the ionospheric slab thickness during one year of low solar activity,” 13th International congress of the Brazilian Geophysical Society Rio de Janeiro, Brazil, 2013.
M. Mosert, S. Magdaleno, D. Buresova, D. Altadill, M. Gende, , E. Gularte & L. Scida, “Behavior of the equivalent slab thickness over three European stations,” Adv. Sp. Res., vol. 51, no. 4, pp. 677–682, 2013.
I. E. Zakharenkova, I. V. Cherniak, A. Krankowski, and I. I. Shagimuratov, “Cross-hemisphere comparison of mid-latitude ionospheric variability during 1996-2009: ” Adv. Sp. Res., vol. 53, no. 2, pp. 175–189, 2014.
N. Sardar, A. K. Singh, A. Nagar, S. D. Mishra, S. K. Vijay, “Study of Latitudinal variation of Ionospheric parameters - A Detailed report,” J. Ind. Geophys. Union, vol. 16, no. 3, pp. 113–133, 2012.
J. K. Gupta and L. Singh, “Long term ionospheric electron content variations over Delhi,” Ann. Geophys., vol. 18, no. 12, pp. 1635–1644, 2000.
Y. J. Chuo, “The variation of ionospheric slab thickness over equatorial ionization area crest region,” J. Atmos. Solar-Terrestrial Phys., vol. 69, no. 8, pp. 947–954, 2007.
B. Jayachandran, T. N. Krishnankutty, T. L. Gulyaeva, “Climatology of ionospheric slab thickness ” Ann. Geophys., vol. 22, no. 1, pp. 25–33, 2004.
D. S. V. V. D. Prasad, K. Niranjan, and P. V. S. Rama Rao, “TEC and Equivalent Slab-Thickness at Low and Mid latitudes - A Comparative study,” Indian J. Radio Sp. Phys., vol. 16, pp. 295–299, 1987.
P. R. Fagundes, D. S. V. V. D. Prasad, C. M. Denardini, A. J. de Abreu, de Jesus, R., & Gende, M.., “Day-to-day variability of EEJ and its role on EIA over the Indian and Brazilian sectors,” Jgr, pp. 1–14, 2015.
B. O. Adebesin, B. J. Adekoya, S. O. Ikubanni, S. J. Adebiyi, O. A. Adebesin, B. W. Joshua, “Ionospheric electron content and equivalent slab thickness in the equatorial region,” Adv. Sp. Res., vol. 27, no. 3, pp. 1536–1542, 2014.
Copyright (c) 2019 Temitope Pascal Owolabi, Emmanuel Ariyibi, Olatunbosun Lilian, Olabode A.O
This work is licensed under a Creative Commons Attribution 4.0 International License.
The author warrants that the article is original, written by stated author(s), has not been published before, contains no unlawful statements, does not infringe the rights of others, is subject to copyright that is vested exclusively in the author and free of any third party rights, and that any necessary written permissions to quote from other sources have been obtained by the author(s).