Tropical Cyclone‐Induced Gravity Wave Perturbations in the Upper Atmosphere: GITM‐R Simulations

Abstract

The tropical cyclone (TC)‐induced concentric gravity waves (CGWs) are capable of propagating upward from convective sources in the troposphere to the upper atmosphere and creating concentric traveling ionospheric disturbances (CTIDs). To examine the CGWs propagation, we implement tropical cyclone‐induced CGWs into the lower boundary of global ionosphere‐thermosphere model with local‐grid refinement (GITM‐R) and simulate the influence of CGWs on the ionosphere and thermosphere. GITM‐R is a three‐dimensional non‐hydrostatic general circulation model for the upper atmosphere with the local‐grid refinement module to enhance the resolution at the location of interest. In this study, CGWs induced by the typhoon Meranti in 2016 have been simulated. Information of the TC shape and moving trails is obtained from the TC best‐track dataset, and the gravity wave patterns are specified at the lower boundary of GITM‐R (100 km altitude). The horizontal wavelength and phase velocity of wave perturbation at the lower boundary are specified to be consistent with the TEC observations. The simulation reveals a clear evolution of CTIDs, which shows reasonable agreement with the GPS‐TEC observations. This is the first time the typhoon‐driven TEC perturbation has been simulated in a general circulation model. To further examine the dependence of the CTIDs on the wavelength and frequency of the gravity wave perturbation at the lower boundary, different waveforms have been tested as well. The magnitude of CTIDs has a negative correlation with the period but a positive correlation with the wavelength when the horizontal phase velocities are sufficiently fast against the critical‐level absorption.

Detection and Three‐Dimensional Reconstruction of Concentric Traveling Ionosphere Disturbances Induced by Hurricane Matthew on 7 October 2016

“…Since the background values of electron density were smaller at 100–250 km altitudes, the percentage of electron density disturbances was significant in this altitude range, which was comparable to the simulation results of Zhao et al. (2020). Moreover, some small‐amplitude wave‐like disturbances during 6:30 and 8:00 UT were more salient in Figure 11b.…”

“…The horizontal propagation parameters of the CTIDs obtained using GNSS-TEC in this study are comparable to those in previous studies. Zhao et al (2020) obtained a similar time-distance-disturbance relationship (Figure 6) in the simulation of tropical cyclone-induced CGWs.…”

“…Zhao et al. (2020) obtained a similar time‐distance‐disturbance relationship (Figure 6) in the simulation of tropical cyclone‐induced CGWs.…”

Statistical Study of F‐Region Short Period Ionospheric Disturbances Related to Convection in the Lower Atmosphere Over Wuhan, China

“…They found that the TIDs are most likely induced by secondary gravity waves from local horizontal body forces created by the dissipation of primary gravity waves from deep convection. These findings have also been confirmed by other studies (Liu et al, 2021;Maurya et al, 2019;Miyoshi et al, 2018;Snively & Pasko, 2008;Vadas & Becker, 2018;Zhao et al, 2020). To date, the effects of convective activity on the ionosphere have various explanations.…”

Impacts of Different Causes on the Inter‐Hemispheric Asymmetry of Ionosphere‐Thermosphere System at Mid‐ and High‐Latitudes: GITM Simulations

“…It explicitly solves for the densities, velocities, and temperatures of neutrals, ions, and electrons in the spherical coordinate system. Unlike most GCMs used in the community, GITM relaxes the hydrostatic assumption which allows propagations of acoustic waves (Deng et al, 2008(Deng et al, , 2011Lin et al, 2017;Zhao et al, 2020;Zhu et al, 2017) and gives a more accurate description of high-frequency gravity wave propagation (Deng & Ridley, 2014). More details about GITM can be found in Ridley et al (2006).…”