A method of implementing a real-time screening process for amplitude scintillation, the method comprising: detecting an amplitude scintillation event (16-1) in the ionosphere during a sample time period at an amplitude scintillation monitor , wherein detecting the amplitude scintillation event (16-1) during the sample time period at the amplitude scintillation monitor comprises determining an amplitude scintillation monitor discriminator (S4 ij (k)) in a current (k th ) sample time period based on the signal to noise ratio (SNR) power level for at least one reference receiver/satellite pair (RR i /SV j ) meets exclusion criteria; excluding associated satellite measurement data from further use based on the detection of the amplitude scintillation event (16-1) at the amplitude scintillation monitor ; detecting an end to the amplitude scintillation event at the amplitude scintillation monitor based at least in part on the determined amplitude monitor discriminator in the current sample time period; and readmitting excluded satellite measurement data collected after the end of the amplitude scintillation event as determined by the amplitude scintillation monitor by: counting the number of samples for which the amplitude scintillation monitor discriminator for an excluded reference receiver/satellite pair is less than a readmit threshold (S4 READMIT THRESHOLD); comparing the counted number of samples below the threshold that occurred prior to the current sample time period and after the reference receiver/satellite pair was excluded to a preselected number of samples (P). detecting an amplitude scintillation event (16-1) in the ionosphere during a sample time period at an amplitude scintillation monitor , wherein detecting the amplitude scintillation event (16-1) during the sample time period at the amplitude scintillation monitor comprises determining an amplitude scintillation monitor discriminator (S4 ij (k)) in a current (k th ) sample time period based on the signal to noise ratio (SNR) power level for at least one reference receiver/satellite pair (RR i /SV j ) meets exclusion criteria; excluding associated satellite measurement data from further use based on the detection of the amplitude scintillation event (16-1) at the amplitude scintillation monitor ; detecting an end to the amplitude scintillation event at the amplitude scintillation monitor based at least in part on the determined amplitude monitor discriminator in the current sample time period; and readmitting excluded satellite measurement data collected after the end of the amplitude scintillation event as determined by the amplitude scintillation monitor by: counting the number of samples for which the amplitude scintillation monitor discriminator for an excluded reference receiver/satellite pair is less than a readmit threshold (S4 READMIT THRESHOLD); comparing the counted number of samples below the threshold that occurred prior to the current sample time period and after the reference receiver/satellite pair was excluded to a preselected number of samples (P). counting the number of samples for which the amplitude scintillation monitor discriminator for an excluded reference receiver/satellite pair is less than a readmit threshold (S4 READMIT THRESHOLD); comparing the counted number of samples below the threshold that occurred prior to the current sample time period and after the reference receiver/satellite pair was excluded to a preselected number of samples (P). <EOS>