IIA Institutional Repository

Range and frequency spread-F at Kodaikanal

Show simple item record

dc.contributor.author Sastri, J. H
dc.contributor.author Sasidharan, K
dc.contributor.author Subramanyam, V
dc.contributor.author Srirama Rao, M
dc.date.accessioned 2009-11-13T12:47:49Z
dc.date.available 2009-11-13T12:47:49Z
dc.date.issued 1979-09
dc.identifier.citation Annales De Geophysique, Vol. 35, No. 3, pp. 153 - 158 en
dc.identifier.issn 0011-3891
dc.identifier.uri http://hdl.handle.net/2248/4907
dc.description.abstract Using ionogram data at Kodaikanal (geomagnetic lat. 06 deg N, Dip 3.5 deg N) over a seven year period, Jan. 1957-Dec. 1963, a study is made of the seasonal and sunspot cycle variations in the nocturnal occurrence of amplitude and frequency type of spread-F configurations. It is found that the occurrence of both amplitude and frequency type spread-F exhibits a positive dependence on the phase of the sunspot cycle. There is also a significant positive correlation between the occurrence patterns of amplitude and frequency type spread-F. The occurrence of amplitude type spread-F shows a prominent peak around 20-22 hrs LT, irrespective of season and phase of the sunspot cycle, except during local summer months of low sunspot years when it is shifted to the postmidnight period around 00-03 hrs LT. The peak occurrence of amplitude spread-F (for two hours around the peak) shows a semi-annual variation during years of moderate and low sunspot activity. A comparison of these results with those at other equatorial stations revealed a marked longitudinal dependence of the characteristics (nocturnal, seasonal and sunspot cycle changes) of amplitude and frequency type spread-F. en
dc.language.iso en en
dc.publisher European Geophysical Society en
dc.subject Equatorial Atmosphere en
dc.subject Nocturnal Variations en
dc.subject Solar Activity Effects en
dc.subject Solar Terrestrial Interactions en
dc.subject Spread F en
dc.subject Annual Variations en
dc.subject Ionograms en
dc.subject Sunspot Cycle en
dc.title Range and frequency spread-F at Kodaikanal en
dc.type Article en

Files in this item

This item appears in the following Collection(s)

Show simple item record

Search DSpace


My Account