The first real-time worldwide ionospheric predictions network: An advance in support of spaceborne experimentation, on-line model validation, and space weather

• Published in: Geophysical research letters Vol. 25; no. 4; pp. 449 - 452
• Main Authors: Szuszczewicz, E. P., Blanchard, P., Wilkinson, P., Crowley, G., Fuller-Rowell, T., Richards, P., Abdu, M., Bullett, T., Hanbaba, R., Lebreton, J. P., Lester, M., Lockwood, M., Millward, G., Wild, M., Pulinets, S., Reddy, B. M., Stanislawska, I., Vannaroni, G., Zolesi, B.
• Format: Journal Article
• Language: English; Russian
• Published: Washington, DC Blackwell Publishing Ltd 15.02.1998; American Geophysical Union
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/97GL03279

We report on the first realtime ionospheric predictions network and its capabilities to ingest a global database and forecast F‐layer characteristics and “in situ” electron densities along the track of an orbiting spacecraft. A global network of ionosonde stations reported around‐the‐clock observations of F‐region heights and densities, and an on‐line library of models provided forecasting capabilities. Each model was tested against the incoming data; relative accuracies were intercompared to determine the best overall fit to the prevailing conditions; and the best‐fit model was used to predict ionospheric conditions on an orbit‐to‐orbit basis for the 12‐hour period following a twice‐daily model test and validation procedure. It was found that the best‐fit model often provided averaged (i.e., climatologically‐based) accuracies better than 5% in predicting the heights and critical frequencies of the F‐region peaks in the latitudinal domain of the TSS‐1R flight path. There was a sharp contrast, however, in model‐measurement comparisons involving predictions of actual, unaveraged, along‐track densities at the 295 km orbital altitude of TSS‐1R. In this case, extrema in the first‐principle models varied by as much as an order of magnitude in density predictions, and the best‐fit models were found to disagree with the “in situ” observations of Ne by as much as 140%. The discrepancies are interpreted as a manifestation of difficulties in accurately and self‐consistently modeling the external controls of solar and magnetospheric inputs and the spatial and temporal variabilities in electric fields, thermospheric winds, plasmaspheric fluxes, and chemistry.