Correlation in f0F2 and M(3000) F2 variations in South-West Europe

A statistical analysis of the variations of the hourly daily values of the M(3000)F2 with the corresponding values of critical frequencies f0F2 was provided for two similar ionosondes (Digisonde-256) located in El Arenosillo and Geophysical Observatory Ebro (both in Spain). Data for winter 1993/1994 and summer 1993 are presented. It is shown that for hour-to-hour variations (both seasons) and for day-to-day variations in summer the correlation is poor and contradictory but for the day-to-day variations in winter months the correlation is significantly higher and positive.