Controlling current conditions of signal propagation of navigation satellites

We suggest using the S4 scintillation index to control the current radiowave propagation condition and radio navigation parameter measurement quality by signals from individual GPS satellites. We corroborate the possibility to use the S4 index for the above purposes by example of simultaneous observations of navigation-temporal positioning errors via applying user´s GPS/ GLONASS MRK-19L navigation equipment and current geomagnetic conditions during the 2004 November 9 powerful magnetic storm.