E and F Region Predictions for Communication Purposes at High Latitudes

Abstract

This paper presents a summary of the report of Working Group C2 [Hunsucker et al. 1980] (High-1 atitude E and F Region Ionospheric Predictions) at the Internationa1 Solar-Terrestria 1 Predictions (ISTP) Workshop held in Boulder, Colorado, April 23–27, 1979. The members of Working Group C2 were: Chairman, R. Hunsucker; Members: R. Allen, P. Argo, R. Babcock, P. Bakshi, D. Lund, S. Matsushita, G. Smith, A. Shirochkov, and G. Wortham. These conference report results will be supplemented by the inclusion of material published since the end of the ISTP Workshop. ISTP WG C2 was concerned about the morphology, phenomenology and parameter prediction of the E and F-layers at latitudes greater than Λ = 60°. Several survey papers treating this topic have been published in the period starting with the International Geophysical Year (IGY) such as those by Agy [1957], Penndorf and Coroniti [1959], Kirby and Little [1960], Gassmann [1963], Landmark [1964], Hunsucker [1967], Folkestad [1968], Hunsucker and Bates [1969], Bates and Hunsucker [1974, Thrane [1979], and Hunsucker [1980]. Unfortunately most of the E and F layer information described in the preceding reports pertains to the latitude range Λ ≃ 60°-75°. Our knowledge of the main features of ionization below the F2 peak in the region of Λ ≃ 75°-90° is at best sketchy, making realistic predictions on most HF transpolar paths extremely difficult.