A global model for the height of the F2-peak using M3000 values from the CCIR numerical map

The International Radio Consultative Committee (CCIR) has established a mapping procedure for monthly median M(3000)F2 (a factor which gives the ratio of the maximum usable frequency over a distance of 3000 km and vertical critical frequency). The present paper compares different methods for obtaining the peak altitude hmF2 using CCIR M3000 values the study is a contribution to the International Reference Ionosphere Project. It is found that global descriptive models are improved when more coefficients are used in particular, Dudeney's relation and that of Bilitza-Eyfrig-Sheikh were found to be satisfactory.