Simultaneous Observations of a Sporadic E Layer by Digisonde and SuperDARN HF Radars at Zhongshan, Antarctica

Abstract

Sporadic E (Es) layers could be composed of metallic ions and formed, modified, or transported by the action of convective electric fields in the high latitude ionosphere. In this paper, by utilizing simultaneous observations from Digisonde and Super Dual Auroral Radar Network (SuperDARN) HF radars at Zhongshan Station (ZHS, 69.4°S, 76.4°E), Antarctica, a thin Es layer, which initially formed in the lower F region and descended into the lower E region, with wavelike structures, was recorded by Digisonde on 14 November 2019. The Es layer‐related concurrent ionospheric irregularities were also detected by the SuperDARN ZHS HF radar. By using a global‐scale 2‐D convection map, combined with images from the Special Sensor Ultraviolet Spectrographic Imager instruments onboard Defense Meteorological Satellite Program (DMSP) spacecraft, it is proposed that the flow shears associated with the duskside convective circulation are responsible for the evolution of the Es layer. Moreover, using the HF radar elevation angle data to measure the scatter height, it is strongly suggested that the Es layer was elongated with convection circulation. The electrodynamic processes responsible for the formation and evolution of the Es layer are discussed.

Solitary wave characteristics on the fine structure of the mesospheric sporadic sodium layer

“…This implies that vertical wind speed has a non-linear function in this Na S event, influencing the sodium density transfer. As stated in previous studies (Chen et al, 2021a;Chen et al, 2021b), Na S is also modulated by the horizontal wind field. Figures 5C-E show the zonal wind, meridional wind, and the temperature profiles, respectively.…”

Mesoscale Auroral Curls in Antarctica

“…The diameter of the field‐of‐view (FOV) is about 1,000 km at an altitude of 150 km. Ionospheric flow data measured by the high frequency (HF) radar at ZHS (10.2–10.4 MHz) are used as well, which is a part of the Super Dual Auroral Radar Network (SuperDARN, Chisham et al., 2007) with the code “ZHO.” This radar scans through 16 uniformly distributed beams with an azimuthal separation of ∼3.24° and produces a fan‐shaped FOV map every minute (Chen et al., 2022; Greenwald et al., 1985, 1995). For each beam, the dwell time is 3 s and 75 range gates are sampled with a gate length of 45 km (Liu et al., 2011; Jiang et al., 2022).…”