Wavenumber‐4 Patterns of the Sporadic E Over the Middle‐ and Low‐Latitudes

Liu, Zhendi; Fang, Hanxian; Yue, Xinan; Lyu, Huijuan

doi:10.1029/2021ja029238

Cited by 11 publications

(10 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Herein, the wave‐4 structure of the diurnal tidal amplitudes can further explain the results of Liu et al. (2021) and Niu (2021). Note that compared with other seasons, the amplitude of the DE3 in winter is the smallest, which could explain that the diurnal tide does not present the wave‐4 structure in winter.…”

Section: Discussion and Summarysupporting

confidence: 71%

“…Recent researcher (e.g., Liu et al, 2021;Niu, 2021) found the wavenumber 4 pattern in Es layer intensity and Es layer occurrence rate at low latitudes. Herein, the wave-4 structure of the diurnal tidal amplitudes can further explain the results of Liu et al (2021) and Niu (2021). Note that compared with other seasons, the amplitude of the DE3 in winter is the smallest, which could explain that the diurnal tide does not present the wave-4 structure in winter.…”

Section: Discussion and Summarymentioning

confidence: 99%

See 1 more Smart Citation

Global Structure and Seasonal Variations of the Tidal Amplitude in Sporadic‐E Layer

et al. 2022

View full text Add to dashboard Cite

Sporadic-E (Es) layer is an enhanced ionization patch composed of metallic ions (Fe + , Mg + , Na + , and Ca + ) derived from meteor deposition and ablation that appears in the mesosphere and the lower thermosphere (MLT) region. Observation and simulation results have demonstrated that Es layer formation over the middle and low latitude regions is attributed to neutral wind shear theory, in which the zonal and meridional winds provide vertical wind shear nulls where the long-lived metallic ions converge and form a thin layer of intense metallic ionization (Haldoupis, 2012;Mathews, 1998;Whitehead, 1989). Compared with the electron density of the background ionospheric E layer, the much higher electron density in the thin layer and strong vertical electron density gradient cause irregular propagation of HF/VHF radio waves, and hence affect navigation systems, radio communications,

show abstract

Section: Discussion and Summarysupporting

confidence: 71%

Section: Discussion and Summarymentioning

confidence: 99%

Global Structure and Seasonal Variations of the Tidal Amplitude in Sporadic‐E Layer

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Furthermore, the longitudinal wavenumber‐4 (WN4) structure is observed in the occurrence and intensity of E s layers at low latitudes and midlatitudes (Z. Liu, Fang, et al., 2021; Z. Liu, Li, et al., 2021; Niu, 2021b; Niu et al., 2019). The occurrence of the WN4 structures strongly depends on the season.…”

Section: Model Variablesmentioning

confidence: 99%

An Empirical Model of the Ionospheric Sporadic E Layer Based on GNSS Radio Occultation Data

Xue

Scott

et al. 2022

Space Weather

Self Cite

View full text Add to dashboard Cite

The intense plasma irregularities within the ionospheric sporadic E (Es) layers at 90–130 km altitude have a significant impact on radio communications and navigation systems. As a result, the modeling of the Es layer is very important for the accuracy, reliability, and further applications of modern real‐time global navigation satellite system precise point positioning. In this study, we have constructed an empirical model of the Es layer using the multivariable nonlinear least‐squares‐fitting method, based on the S4max from Constellation Observing System for Meteorology, Ionosphere, and Climate satellite radio occultation measurements in the period 2006–2014. The model can describe the climatology of the intensity of Es layers as a function of altitude, latitude, longitude, universal time, and day of year. To validate the model, the outputs of the model were compared with ionosonde data. The correlation coefficients of the hourly foEs and the daily maximum foEs between the ground‐based ionosonde observations and model outputs at Beijing are 0.52 and 0.68, respectively. The model can give a global climatology of the intensity of Es layers and the seasonal variations of Es layers, although the Es layers during the summer are highly variable and difficult to accurately predict. The outputs of the model can be implemented in comprehensive models for a description of the climatology of Es layers and provide relatively accurate information about the global variation of Es layers.

show abstract

“…Terdiurnal and querterdiurnal tidal signatures in Es occurrence rate are also indicated in other publications (e.g., Haldoupis & Pancheva, 2006;Fytterer et al, 2013;Jacobi et al, 2019). Recently, Liu et al (2021) revealed a wavenumber 4 pattern in Es occurrence rate at mid and low latitudes formed by eastward propagating non-migrating diurnal tide with zonal wavenumber 3, and a similar feature was detected in the vertical shear of the zonal wind. Shinagawa et al (2017) calculated the vertical ion convergence rate using GAIA (Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy) simulations to show how the geographical and seasonal variations of wind shears are consistent with those in EsOR.…”

Section: Introductionmentioning

confidence: 63%

Comparison of the Tidal Signatures in Sporadic E and Vertical Ion Convergence Rate, Using FORMASAT-3/COSMIC Radio Occultation Observations and GAIA Model

Sobhkhiz-Miandehi

Yamazaki

Arras

et al. 2021

Preprint

View full text Add to dashboard Cite

Sporadic E or Es is a transient phenomenon where thin layers of enhanced electron density appear in the ionospheric E region (90-120 km altitude). The neutral wind shear caused by atmospheric tides can lead ions to converge vertically at E-region heights and form the Es layers. This research aims to determine the role of atmospheric solar and lunar tides in Es occurrence. For this purpose, radio occultation data of FORMASAT-3/COSMIC have been used, which provides complete global coverage of Es events. Moreover, GAIA model simulations have been employed to evaluate the vertical ion convergence induced by solar tides. The results show both migrating and non-migrating solar tidal signatures and the semidiurnal migrating lunar tidal signature in Es occurrence. The seasonal variation of the migrating solar tidal components of Es is in good agreement with those in the vertical ion convergence derived from GAIA. Furthermore, some non-migrating components of solar tides, including semidiurnal westward wavenumbers 1 and 3 and diurnal eastward wavenumbers 2 and 3, also significantly affect the Es occurrence rate.

show abstract

Wavenumber‐4 Patterns of the Sporadic E Over the Middle‐ and Low‐Latitudes

Cited by 11 publications

References 48 publications

Global Structure and Seasonal Variations of the Tidal Amplitude in Sporadic‐E Layer

Global Structure and Seasonal Variations of the Tidal Amplitude in Sporadic‐E Layer

An Empirical Model of the Ionospheric Sporadic E Layer Based on GNSS Radio Occultation Data

Comparison of the Tidal Signatures in Sporadic E and Vertical Ion Convergence Rate, Using FORMASAT-3/COSMIC Radio Occultation Observations and GAIA Model

Contact Info

Product

Resources

About