Quality control of automatically scaled vertical incidence ionogram data


  • R. O. Conkright,

  • L. F. McNamara


Software procedures are described for the routine scanning of data sets from automatically scaled vertical incidence ionograms, with a view to identifying ionograms which have been incorrectly scaled. Such procedures have been made necessary by the increasing use of real-time ionospheric data in operational systems and by the increasing flow of such data into the U.S. National Geophysical Data Center (NGDC), which have made the required data-scanning functions overwhelming for a human operator. The procedures will detect pathological data sets and prevent them from being passed on to the operational system or to NGDC databases, as well as indicating unusual ionospheric conditions and possibly the need for modifications of the automated procedures. Particular reference is made to the SAO (standard ARTIST output) files created by the University of Massachusetts Lowell program ADEP (ARTIST display and editing program) and corresponding to ionograms obtained using a Digisonde and scaled in real time by ARTIST (automatic real-time ionogram scaling with true-height). These files were chosen because of their ready availability at NGDC and because they cover a wide range of latitudes, seasons, and ionospheric conditions. Similar procedures can readily be developed for other ionogram data sets. The basic change would be to the function which reads in the data, although experience will probably lead to the inclusion of procedures to counter idiosyncrasies of the ionogram scaling procedures, such as have been found with ARTIST.