Pre-assessment of the "strength" and "latitudinal extent" of L-band scintillation: A case study

• Published in: Journal of geophysical research. Space physics 2013-01, Vol.118 (1), p.488-495
• Main Authors: Bagiya, Mala S., Sridharan, R., Sunda, S.
• Format: Article
• Language: English
• Subjects: Equatorial Spread-F; Geophysics; Latitude; Latitudinal extent of the L-band scintillation; Strength of the L-band scintillation
• ISSN: 2169-9380; 2169-9402
• DOI: 10.1029/2012JA017989

Forecasting the strength of nighttime L‐band scintillation well in advance of their actual occurrence by making use of the background conditions has been attempted over the Indian zone with an eye on operational forecasting capability. It has been shown that the base height of the equatorial F‐region as early as 1930 h LT shows a linear relation to the maximum altitudinal extent of medium‐scale irregularities that are responsible for the L‐band scintillation during the course of the night and these in turn get mapped to latitudes away from the equator defining the latitude range that gets affected by their presence. On the other hand, the average value of the vertical total electron content between 1830 h LT and 1930 h LT on a given day is shown to control the maximum strength of the scintillation represented by S4 index on the day. The above analysis, although it has been carried out for the equatorial station Trivandrum, is applicable to other latitudes as well. Having demonstrated the control of the background ionospheric‐thermospheric conditions, it has been shown that the averaged vertical total electron content around the prereversal enhancement (1830 h LT to 1930 h LT) along with the actual base height information at 1930 h LT over the magnetic equator would enable one to forecast the maximum possible S4 in a given latitudinal region as early as 1930 h and issue necessary forewarning alerts wherever needed. Key Points The averaged VTEC is shown to control the strength of L‐band scintillation The h‐F at 1930 LT is shown to control the latitudinal extent of scintillation The observed strength fall below the predicted limits irrespective of location