Indices for Prediction of f₀F₂

ABSTRACT

For forecasting critical frequencies of F₂-layer, the use of sunspot number does not lead to correct results as the correlation between these two often shows large deviations. The possibility of using the variation of Solar Flux at 2800 Mc/s. in place of sunspot number is considered. It is pointed out that for long term prediction of f₀F₂ the solar flux at 2800 Mc/s. has no additional advantage over the sunspot number.