The comparative analysis of Omnipresent Coherent Fluctuations in the Ionosphere and A-maps amplitude variation

Recent observations of the incoherent scatter radar (ISR) power profile at Arecibo, Millstone Hill, and Poker Flat AMISR showed the constant presence of continuous quasi-periodic waves with periods of about 1 hour in F region. This phenomenon was called as the Coherent Omnipresent Fluctuations in the Ionosphere (COFIs) (Livneh et al. [2007]; Livneh et al. [2009]). Such variations present around the clock. Therefore, the nature of their origin is not clear. These fluctuations have a lot of cumulative similarity with the TIDs, which observed with coherent scatter radar.