Rare observations of sprites and gravity waves supporting D, E, F-regions ionospheric coupling

Abstract

We report rare simultaneous observations of columniform sprites and associated gravity waves (GWs) using the Transient Luminous Events (TLEs) camera and All-sky imager at Prayagraj (25.5° N, 81.9° E, geomag. lat. ~ 16.5° N), India. On 30 May 2014, a Mesoscale Convective System generated a group of sprites over the north horizon that reached the upper mesosphere. Just before this event, GWs (period ~ 14 min) were seen in OH broadband airglow (emission peak ~ 87 km) imaging that propagated in the direction of the sprite occurrence and dissipated in the background atmosphere thereby generating turbulence. About 9–14 min after the sprite event, another set of GWs (period ~ 11 min) was observed in OH imaging that arrived from the direction of the TLEs. At this site, we also record Very Low Frequency navigational transmitter signal JJI (22.2 kHz) from Japan. The amplitude of the JJI signal showed the presence of GWs with ~ 12.2 min periodicities and ~ 18 min period. The GWs of similar features were observed in the ionospheric Total Electron Content variations recorded at a nearby GPS site. The results presented here are important to understand the physical coupling of the troposphere with the lower and upper ionosphere through GWs.

Role of Lightning Activity in Deciphering Atmospheric Gravity Waves (AGWs) Induced D‐Region Ionospheric Perturbations During Extremely Severe Cyclonic Storm (ESCS) Fani

“…As mentioned in the previous section the D‐region of the ionosphere is very stable during the daytime because of solar ionization. To study perturbations in the D‐region, the nighttime period is ideal (e.g., Kabirzadeh et al., 2017; Maurya et al., 2022). The red line in each panel of Figure 10 is for the NWC signal variations on respective days.…”

Geomagnetic Storm Associated D‐Region Anomalies Estimated From VLF Observations at a Low‐Latitude Station, Suva, Fiji

“…Recently, Maurya et al. (2021) based on the simultaneous imaging of sprites and GWs using a TLE (Transient Luminous Events) camera, an all‐sky airglow imager, narrowband VLF signals and GPS (Global Positioning System) total electron content observations have supported the coupling of the lower ionosphere (D and E regions) with the upper ionosphere (F‐region) through AGWs generated by the tropospheric mesoscale convective system. Peter et al.…”

Earthquakes associated subionospheric VLF anomalies recorded at two low latitude stations in the South Pacific region

“…The induced EQ vertical electric field of 1000 mV/m at a height more than 60 km over EQ active region a few days before the seismic activity penetrates the ionosphere and perturbs the ionospheric electrodynamics and the electron density by changing the F-region E × B plasma drifts (Pulinets et al, 1998). The lower ionosphere can be perturbed due to the coupling of the lower ionosphere with the upper ionosphere (Ohya et al, 2006;Maurya et al, 2022).…”