Analysis of daytime ionosphere behavior between 2004 and 2008 in Antarctica

Correia, E.; Kaufmann, P.; Raulin, J. P.; Bertoni, F.; Gavilán, Hernan R.

doi:10.1016/j.jastp.2011.06.008

Cited by 23 publications

(11 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The first comparison between VLF NB amplitude and the SABER temperature profile showed that in most cases the highest anticorrelation was between the NB amplitudes and mesopause temperatures. Although VLF NB amplitudes were already associated in previous studies to the dynamics and temperatures of the stratosphere [e.g., Correia et al ., ], the relation between VLF NB amplitudes and mesopause temperatures, either direct or indirect, has not been identified previously. However, a connection between mesopause temperatures and radio waves absorption has been predicted before [e.g., Taubenheim , ].…”

Section: Discussionmentioning

confidence: 99%

Links between mesopause temperatures and ground‐based VLF narrowband radio signals

et al. 2013

View full text Add to dashboard Cite

[1] The Upper Mesosphere-Lower Thermosphere (UMLT) region of the atmosphere is known to vary on many temporal and spatial scales. However, this region of the atmosphere is very difficult to measure and monitor continuously. In this paper, we demonstrate an intriguing connection between mesopause temperatures and the intensity of very low frequencies (VLF) narrowband (NB) signals reflected off the lower ionosphere. The temperature data used are from the SABER instrument onboard the TIMED satellite, while the VLF data are obtained from various ground-based receiving systems. The results of the analysis show a high anticorrelation between temperature and VLF amplitude. It is shown that the variability of the UMLT temperatures and VLF amplitudes can be explained by global seasonal solar irradiance changes (~72% of the variability), while the remaining variability has its origins from other sources (~28%). High-resolution mesopause temperature estimates might be achieved in the future by combining VLF NB observations and calculated solar irradiance variability (as a function of hour, day, and location, i.e., latitude).Citation: Silber, I., C. Price, C. J. Rodger, and C. Haldoupis (2013), Links between mesopause temperatures and groundbased VLF narrowband radio signals,

show abstract

Section: Discussionmentioning

confidence: 99%

Links between mesopause temperatures and ground‐based VLF narrowband radio signals

et al. 2013

View full text Add to dashboard Cite

show abstract

“…As a result, the annual VLF signal amplitude variation is not a fixed function of the noon solar zenith angle. Instead, it varies from year to year through the solar cycle as can be seen in Correia et al (2011). The influence of Lyα radiation on diurnal DHO VLF signal amplitude variations is visible the in the Figure 1 through the duration of daytime sections "D" and their changes during the year as seen in the Figure 2.…”

Section: Seasonal Variationsmentioning

confidence: 89%

“…As numerous studies have shown, all these parameters are variable in space and time and they can be calculated from experimental data obtained by various observational techniques. Thus, variations in the Lyα irradiance during solar cycles and seasons are presented in Woods et al (2000), Fröhlich (2009) and Correia, Kaufmann, Raulin, Bertoni, and Gavilan (2011) and results given in Kockarts (2002) exhibit a strong zenith angle dependency of Lyα line absorption coefficients in the atmosphere. Also, measurements of the NO density show values within a wide range at fixed altitudes (Aikin, Kane, & Troim, 1964;Pearce, 1969;Barabash, Osepian, Dalin, & Kirkwood, 2012; and references therein).…”

Section: Introductionmentioning

confidence: 93%

Responses of the ionospheric D-region to periodic and transient variations of the ionizing solar Lyα radiation

Nina¹,

Čadež²,

Bajčetić³

et al. 2017

J GEOGR INST CVIJIC

View full text Add to dashboard Cite

Solar radiation has the most important role in periodical variation of terrestrial atmospheric properties. Under unperturbed ionospheric conditions, the solar Lyα line has a dominant influence on ionization processes in the lowest ionospheric layer, the so called D-region. In this paper, we present periodical and transient variations in influences of the Lyα radiation on this ionospheric layer. In the case of periodical lower ionospheric changes we consider diurnal, seasonal and solar cycle variations and show analysis of acoustic and gravity waves induced by solar terminator. Influences of solar flares and eclipses on this atmospheric layer are analyzed as examples of sudden ionospheric disturbances. For decades, Very Low Frequency radio signals (3-30 kHz) are successfully used as a tool for monitoring of changes in the lower ionosphere, based on radio wave propagation through Earth-ionosphere waveguide along given trajectories and registration of their physical parameters (amplitude and phase delay). For the analysis conducted in this paper, we used records of the VLF DHO signal, emitted on 23.4 kHz frequency from transmitter in Germany and received in Serbia.

show abstract

“…AGWs have been detected as amplitude variations of VLF signals associated with solar terminator motions (Nina and Cadez, 2013), with the passage of tropical cyclones crossing the transmitter-receiver VLF propagation path (Rozhnoi et al, 2014), and particularly during nighttime, in association with local convective and lightning activity (Marshall and Snively, 2014). Planetary wave signatures have also been detected in the VLF NB amplitude data, whose effects are pronounced during wintertime and present a predominant quasi 16 d oscillation (Correia et al, , 2013Schmitter, 2012;Pal et al, 2015).…”

Section: Introductionmentioning

confidence: 99%

Characterization of gravity waves in the lower ionosphere using very low frequency observations at Comandante Ferraz Brazilian Antarctic Station

et al. 2020

View full text Add to dashboard Cite

Abstract. The goal of this work is to investigate the gravity wave (GW) characteristics in the low ionosphere using very low frequency (VLF) radio signals. The spatial modulations produced by the GWs affect the conditions of the electron density at reflection height of the VLF signals, which produce fluctuations of the electrical conductivity in the D region that can be detected as variations in the amplitude and phase of VLF narrowband signals. The analysis considered the VLF signal transmitted from the US Cutler, Maine (NAA) station that was received at Comandante Ferraz Brazilian Antarctic Station (EACF, 62.1∘ S, 58.4∘ W), with its great circle path crossing the Drake Passage longitudinally. The wave periods of the GWs detected in the low ionosphere are obtained using the wavelet analysis applied to the VLF amplitude. Here the VLF technique was used as a new aspect for monitoring GW activity. It was validated comparing the wave period and duration properties of one GW event observed simultaneously with a co-located airglow all-sky imager both operating at EACF. The statistical analysis of the seasonal variation of the wave periods detected using VLF technique for 2007 showed that the GW events occurred all observed days, with the waves with a period between 5 and 10 min dominating during night hours from May to September, while during daytime hours the waves with a period between 0 and 5 min are predominant the whole year and dominate all days from November to April. These results show that VLF technique is a powerful tool to obtain the wave period and duration of GW events in the low ionosphere, with the advantage of being independent of sky conditions, and it can be used during the whole day and year-round.

show abstract

Analysis of daytime ionosphere behavior between 2004 and 2008 in Antarctica

Cited by 23 publications

References 52 publications

Links between mesopause temperatures and ground‐based VLF narrowband radio signals

Links between mesopause temperatures and ground‐based VLF narrowband radio signals

Responses of the ionospheric D-region to periodic and transient variations of the ionizing solar Lyα radiation

Characterization of gravity waves in the lower ionosphere using very low frequency observations at Comandante Ferraz Brazilian Antarctic Station

Contact Info

Product

Resources

About