A statistical analysis of equatorial plasma bubble structures based on an all‐sky airglow imager network in China. Issue 11 (22nd November 2016)

• Record Type: Journal Article
• Authors: Sun, Longchang; Xu, Jiyao; Wang, Wenbin; Yuan, Wei; Li, Qinzeng; Jiang, Chaowei
• Is Part Of: Journal of geophysical research. Volume 121:Issue 11(2016:Nov.)
• Page Start: 11, 495
• Page End: 11, 517
• Publication Date: 2016-11-22
• Subjects: equatorial plasma bubbles (EPBs) -- all‐sky airglow imager network -- statistical features; Magnetospheric physics -- Periodicals; Space environment -- Periodicals; Cosmic physics -- Periodicals; Planets -- Atmospheres -- Periodicals; Heliosphere (Astrophysics) -- Periodicals; Geophysics -- Periodicals; 523.01
• DOI: 10.1002/2016JA022950
• Languages: English
• ISSNs: 2169-9380

Abstract

Abstract: This paper investigates the statistical features of equatorial plasma bubbles (EPBs) using airglow images from 2012 to 2014 from a ground‐based network of four imagers in the equatorial region of China. It is found that (1) EPBs mainly occur during 21:00–00:00 local time (LT) in equinoxes. There is an asymmetry in occurrence rates between March (June) and September equinoxes (December solstices). (2) Most EPBs occur in groups of two to six depletions. The distance between adjacent EPB depletions is ~100–700 km, and the average is 200–300 km. The zonal extension of an EPB group is usually less than 1500 km but can reach 3000 km. (3) EPBs usually have a maximum drift velocity near 100 m/s at 21:00–22:00 LT in 9.5° ± 1.5° geomagnetic latitude and then decrease to 50–70 m/s toward sunrise. (4) The averaged westward tilt angle of most EPBs (with respect to the geographic north‐south) increased from 5°–10° to 23°–30° with LT between 20:00 and 03:00 LT, then decreasing to 10°–20° toward sunrise. (5) When 90 < F 10.7 < 140, the maximum magnetic latitudinal extension (PMLE) is usually lower than 15.0° (apex height ~725 km), but it can reach 23.0° (apex height ~1330 km) when F 10.7 > 140. The maximum PMLE increases by 3.4°–5.5° when F 10.7 changes from 90 to 190. (6) The EPB occurrence patterns and zonal drift velocities are significantly different from those at Kolhapur, India, which locates west to our stations by 20.0°–32.0° in longitude. Key Points: Daily and seasonal variations of EPB occurrence pattern, zonal drift velocity, and polarward magnetic latitude extension in China Statistical features of the distance, longitudinal extension, and tilt of EPB depletions Distinct differences in EPB occurrence pattern and zonal drift velocities between China and Kolhapur, India