Occurrences of Regional Strong Es Irregularities and Corresponding Scintillations Characterized Using a High‐Temporal‐Resolution GNSS Network

Strong sporadic E (E-s) irregularities over China are investigated based on high-temporal-resolution total electron content (TEC) derived from two crossed chains of Beidou geostationary satellite (BD-GEO) TEC receivers along 110 degrees E and 23 degrees N, respectively. The high resolution rate of TEC index (HR-ROTI) calculated at an interval of 30 s, is proposed to characterize small-scale strong E-s irregularity structures. Based on the HR-ROTI measurements and the typical drift velocity of E-s 60 m/s, the scale sizes of strong E-s irregularity structures were revealed to be mainly similar to 7 km. The structures were mostly quasi-periodically separated with distances of 7-16 km. Through a further statistical analysis of strong E-s irregularity structures along the two chains, it was found that the E-s irregularity structures predominantly occur during local summer at middle and low latitudes, with the occurrence rate peaking at similar to 30 degrees N. On average approximately 2-5 small-scale strong E-s irregularity structures may be embedded in one larger-scale structure. Unlike the equatorial and low-latitude F-region irregularities which cause scintillations under most conditions, the strong E-s irregularity characterized by HR-ROTI caused scintillation with relatively low occurrence rates of 37% and 12% at middle and low latitudes, respectively.