Improved world-wide maps of monthly median f0F2

New global maps of monthly median values of f0F2 have been prepared using over 45,000 station months of f0F2 observations, semiempirical model values of f0F2 in the midlatitude ocean areas and empirical model values for the equatorial and high latitude regions. These observations have been carefully screened and mapped, using the Jones-Galley (1965) technique, to produce monthly median maps of f0F2 for each hour, each month and for high and low levels of solar activity.