VariabilityoffoF2 at Low Latitude during High, Moderate and Low Solar Activity

VariabilityoffoF2 at Low Latitude during High, Moderate and Low Solar Activity

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2017 by IJETT Journal
Volume-44 Number-2
Year of Publication : 2017
Authors : Geeta Khoobchandani, S.D Mishra, S.K Vijay
DOI :  10.14445/22315381/IJETT-V44P211

Citation 

Geeta Khoobchandani, S.D Mishra, S.K Vijay"VariabilityoffoF2 at Low Latitude during High, Moderate and Low Solar Activity", International Journal of Engineering Trends and Technology (IJETT), V44(2),57-60 February 2017. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group

Abstract
In the present work we studied day to day variability of the F region of the ionosphere at low latitude station Darwin (120S,1310E)of Australia during the high, moderate and low solar activity period of 23rd solar cycle. We have investigated diurnal, seasonal and annual variability of foF2.The relative standard deviation of hourly values for all the months for the year of High (2000), Moderate (2003) and Low (2008) solar Activity period are analysed to study the variability. To understand the seasonal variation of foF2 more clearly, we have divided the year into five seasons including winter-1 (January and February), equinox-1(March and April), summer (May, June, July and August), equinox-2(September and October) and winter-2(November and December). It has been observed that variability in foF2 is less during day time as compared to night time for moderate (2003) and low (2008) solar activity period.It has also been observed that variability in foF2 is more during pre and post sunset timeas compared to day time for moderate (2003) and low (2008) solar activity period. For high (2000) solar activity period results shows more variability during day time in comparison to night which is an abnormal behaviour.

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Keywords
foF2, Variability, Solar Activity