The Penn State Mk III model produces (1) tables of ionospheric electron densities from 120 km to 1250 km, (2) the ionospheric electron content, and (3) statistical properties of sporadic E occurrence. Two modes of operation are available. One generates two to 24 profiles throughout a day at one location, and the other generates a set of profiles at a range of locations at one universal time. The model combines theoretical computations with empirical models for the F-peak parameters. Mk III is an updated version of the earlier models developed at the Pennsylvania State University by Nisbet (1971) and Lee (1985). It uses the MSIS-83 atmospheric model, solar fluxes measured by the AE-E satellite (Hinteregger and Fukui, 1981), reaction rates from Torr et al. (1979), and the semi-empirical maps for the F-peak parameters developed by Rush et al. (1984). Meanwhile, most of these parameter models have been updated (e.g., see URSI foF2 Model Maps, and the MSIS Model), and these updates should be incorporated into the model code.
Availability: From the authors on one diskette for use on PCs equipped with math co-processor
J. S. Nisbet, On the Construction and Use of a Simple Ionospheric Model, Radio Sci. 6, 437, 1977.
D. G. Torr et al., An Experimental and Theoretical Study of the Mean Diurnal Variation of O+, NO+, O2+, N2+ Ions in the Mid-Latitude F1-Layer of the Ionosphere, J. Geophys. Res. 84, 3360, 1979.
H. E. Hinteregger and K. Fukui, Observational Reference and Model Data on Solar EUV from Measurements on AE-E, Geophys. Res. Lett. 8, 1147, 1981.
C. M. Rush, M. PoKempner, D. N. Anderson, J. Perry, F. G. Stewart, and R. Reasoner, Maps of foF2 Derived from Observations and Theoretical Data, Radio Sci. 19, 1083, 1984.
S. Lee, The Penn State Mark III Ionospheric Model: An IBM XT Computer Code, Pennsylvania State University, Scientific Report PSU CSSL 482, University Park, Pennsylvania, 1985.
NASA Official: Dr. Robert McGuire, Head of the Space Physics Data Facility