Empirical models of parameters B0, B1 from Arecibo radar measurements Original Research Article

High resolution electron density profiles (Ne), measured with the Arecibo incoherent scatter radar (I.S.), are used to obtain the “best fit” bottomside parameters B0 and B1 by comparing the observed profiles with the IRI bottomside profile function. For each profile, the comparison is done for all heights between hmF2 and h0.24 - the altitude where density falls off to quarter of the peak value. However, when a F1 ledge is present, the comparison is limited to altitudes between hmF2 and hmF1. A large ‘day-to-day’ and hour-to-hour variability is seen in both B0 and B1. Median values of these parameters are used to generate empirical models. Comparisons are also made with the IRI model.