Ionospheric plasma bubbles observed concurrently by multi‐instruments over low‐latitude station Hainan

Abstract

Abstract Previous studies have shown that the ionospheric “strong range spread F” (SSF) closely correlates with the occurrence of scintillations caused by equatorial plasma bubbles. However, there is no report on concurrent observations of SSF and bubbles with in situ measurement. This paper discusses two cases of concurrent observations with a DPS4 Digisonde and a collocated scintillation monitor at the low‐latitude station Hainan (19.5°N, 109.1°E), and with in situ ion density measurements made by the ROCSAT‐1 satellite. Two case studies were made for 10 and 23 April 2004, respectively. In both cases, the SSF occurred before midnight and lasted more than 3.5 h. The scintillations were accompanied with strong range SF. Concurrently, the ROCSAT‐1 satellite observed plasma bubbles over Hainan station. In the first case, two bubbles were observed by the satellite with east‐west sizes of more than ~200 km over Hainan station. Two bubbles were also observed in the second case with east‐west extensions of about 220 km and 35 km, respectively. For the first time, direct observational evidence is provided for the causal relationship between equatorial plasma bubbles with in situ measurement and the concurrent occurrence of SSF and strong scintillations.