Options
Grzesiak, Marcin
Loading...
2 results
Now showing 1 - 2 of 2
- PublicationOpen AccessA measure of ionospheric irregularities: zonal velocity and its implications for L-band scintillation at low-latitudes(2021-10-22)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; We estimate the zonal drift velocity of small-scale ionospheric irregularities at low latitude by leveraging the spaced-receivers technique applied to two GNSS receivers for scintillation monitoring installed along the magnetic parallel passing in Presidente Prudente (Brazil, magnetic latitude 12.8°S). The investigated ionospheric sector is ideal to study small-scale irregularities, being located close to the expected position of the southern crest of the equatorial ionospheric anomaly. The measurement campaign took place between September 2013 and February 2014, i.e. equinox and summer solstice seasons under solar maximum, during which the probability of formation of small-scale irregularities is expected to maximize. We found that the hourly average of the velocity increases up to 135 m/s right after the local sunset at ionospheric altitudes and then smoothly decreases in the next hours. Such measurements are in agreement with independent estimations of the velocity made by the Incoherent Scatter Radar located at the Jicamarca Radio Observatory (magnetic latitude 0.1°N), by the Boa Vista Ionosonde (magnetic latitude 12.0°N), and by applying a recently-developed empirical regional short-term forecasting model. Additionally, we investigated the relationship with the percentage occurrence of amplitude scintillation; we report that it is exponentially dependent on the zonal velocity of the irregularities that cause it.670 92 - PublicationOpen AccessRegional Short-Term Forecasting of Ionospheric TEC and Scintillation(2018)
; ; ; ; ; ;; ; ; We describe a novel empirical technique for the regional, short-term (from seconds to minutes) forecasting of both TEC (total electron content) and scintillation indices on Global Navigation Satellite System signals. To provide TEC-forecasted values, the method exploits the continuity equation in the conservative form, while the continuity equation with source term added is used in the case of scintillation forecasting. The performance of the model is investigated, resulting to be satisfactory when applied at equatorial latitudes in Brazil and during postsunset hours, when scintillation phenomena are more likely to occur. Five days affected by strong amplitude scintillation events (S4 > 0.7) are used to test the model performance and evaluate the model accuracy. In addition, the performance of the amplitude scintillation forecasting is evaluated by leveraging on larger statistics. On the average, the forecasting accuracy, in terms of standard deviation of the distributions of the differences between forecasted and actual values, is about 5% for TEC and 15–20% for scintillation parameters.416 34