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Depletion and Traveling Ionospheric Disturbances Generated by Two Launches of China's Long March 4B Rocket

Using total electron content (TEC) data from 902 global navigation satellite system stations over China, we analyzed the ionospheric responses following two similar launches of the Long March 4B from Taiyuan, China, that is, China‐Brazil Earth Resources Satellite 3 launched on 9 December 2013 and China‐Brazil Earth Resources Satellite 4 launched on 7 December 2014. By adopting a method that can detect TEC depletion effectively, filtered TEC series, and built two‐dimensional disturbances map, we found that the ionospheric disturbances of these two launches were almost the same. We identified three types of disturbances following both launches: depletions, shock wave‐related traveling ionospheric disturbances (TIDs), and acoustic wave‐related circle TIDs. The buildup time of depletion was influenced by the amount of exhaust expelled into the ionosphere with an amplitude of ∼12 TEC unit (TECU; 1 TECU = 1016 el/m2). After the electron depletion was formed, it drifted westward for approximately 300 km. The shock wave‐related TIDs can only be observed near the trajectory and reflect the acceleration of the rockets with an amplitude of ∼0.6 TECU. The acoustic wave‐related circle TIDs were observed at the southeast of the launch site. From our observations, this type of TID includes three groups of wave trains, and the speed and period are ∼900 m/s and ∼3.8 min, respectively. The amplitudes of the three groups of TIDs are ∼0.065, ∼0.045, and ∼0.02 TECU.