Mean Zonal Drift Velocities of Plasma Bubbles Estimated from Keograms of Nightglow All-Sky Images from the Brazilian Sector
Abstract
:1. Introduction
2. Data and Methodology
Keograms
3. Results
4. Discussion
5. Summary and Conclusions
- In general, mean zonal drift velocities of EPBs decrease throughout the night. Larger velocity events travel at ≈150 ms−1 (usually occurring during earlier hours of an observation period), while slower events move at ≈60 ms−1 (occurring late in an observation period). The decreasing rate is ≈10 ms−1/h.
- Typically, faster EPBs occur from 20 LT to 23 LT in the west-most region of the zonal keograms in a longitude range of −37° to −33°. The longitudinal gradient in the bubble drift velocity indicates a vertical gradient in the thermospheric wind that controls plasma drifts in the nighttime F region ionosphere. The keogram method can be used to describe these vertical gradients in the thermospheric wind, assuming that the EPBs drift eastward with the zonal wind.
- Our keogram technique compares favorably with the mosaic method [9]. A Gaussian curve fits the velocity differences distribution of well. The standard deviation of the residuals distribution is large (≈15 ms−1). Moreover, >30% of the residuals of have values larger than 15 ms−1, which points out to possible refining of the methods.
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
- Sobral, J.H.A.; Abdu, M.A.; Batista, I.S. Airglow studies on the ionosphere dynamics over low latitude in Brazil. Ann. Geophys. 1980, 36, 199–204. [Google Scholar]
- Sobral, J.H.A.; Abdu, M.A.; Zamlutti, C.J.; Batista, I.S. Association between plasma bubble irregularities and airglow disturbances over Brazilian low latitudes. Geophys. Res. Lett. 1980, 7, 980–982. [Google Scholar] [CrossRef] [Green Version]
- Abdu, M.A.; Muralikrishna, P.; Batista, I.S.; Sobral, J.H.A. Rocket observation of equatorial plasma bubbles over Natal, Brazil, using a high-frequency capacitance probe. J. Geophys. Res. Space Phys. 1991, 96, 7689–7695. [Google Scholar] [CrossRef]
- Abdu, M. Outstanding problems in the equatorial ionosphere–thermosphere electrodynamics relevant to spread F. J. Atmos. Sol.-Terr. Phys. 2001, 63, 869–884. [Google Scholar] [CrossRef]
- Dos Santos Prol, F.; Hernández-Pajares, M.; Tadeu de Assis Honorato Muella, M.; De Oliveira Camargo, P. Tomographic Imaging of Ionospheric Plasma Bubbles Based on GNSS and Radio Occultation Measurements. Remote Sens. 2018, 10, 1529. [Google Scholar] [CrossRef] [Green Version]
- Silva, R.P.; Souza, J.R.; Sobral, J.H.A.; Denardini, C.M.; Borba, G.L.; Santos, M.A.F. Ionospheric Plasma Bubble Zonal Drift Derived From Total Electron Content Measurements. Radio Sci. 2019, 54, 580–589. [Google Scholar] [CrossRef] [Green Version]
- Abalde, J.R.; Fagundes, P.R.; Bittencourt, J.A.; Sahai, Y. Observations of equatorial F region plasma bubbles using simultaneous OI 777.4 nm and OI 630.0 nm imaging: New results. J. Geophys. Res. Space Phys. 2001, 106, 30331–30336. [Google Scholar] [CrossRef] [Green Version]
- Abalde, J.R.; Fagundes, P.R.; Sahai, Y.; Pillat, V.G.; Pimenta, A.A.; Bittencourt, J.A. Height-resolved ionospheric drifts at low latitudes from simultaneous OI 777.4 nm and OI 630.0 nm imaging observations. J. Geophys. Res. Space Phys. 2004, 109. [Google Scholar] [CrossRef] [Green Version]
- Arruda, D.C.S. Study of the Nocturnal Ionosphere F-Layer Zonal Drifts over the Brazilian Region. Ph.D. Thesis, Instituto Nacional de Pesquisas Espaciais (INPE), São José dos Campos, Brazil, 2005. [Google Scholar]
- Arruda, D.C.; Sobral, J.; Abdu, M.; Castilho, V.M.; Takahashi, H.; Medeiros, A.; Buriti, R. Theoretical and experimental zonal drift velocities of the ionospheric plasma bubbles over the Brazilian region. Adv. Space Res. 2006, 38, 2610–2614. [Google Scholar] [CrossRef]
- Sobral, J.; Abdu, M.; Sahai, Y. Equatorial plasma bubble eastward velocity characteristics from scanning airglow photometer measurements over Cachoeira Paulista. J. Atmos. Terr. Phys. 1985, 47, 895–900. [Google Scholar] [CrossRef]
- Sobral, J.H.A.; Abdu, M.A. Latitudinal gradient in the plasma bubble zonal velocities as observed by scanning 630-nm airglow measurements. J. Geophys. Res. Space Phys. 1990, 95, 8253–8257. [Google Scholar] [CrossRef] [Green Version]
- Pimenta, A.; Bittencourt, J.; Fagundes, P.; Sahai, Y.; Buriti, R.; Takahashi, H.; Taylor, M. Ionospheric plasma bubble zonal drifts over the tropical region: A study using OI 630nm emission all-sky images. J. Atmos. Sol.-Terr. Phys. 2003, 65, 1117–1126. [Google Scholar] [CrossRef]
- Takahashi, H.; Taylor, M.J.; Pautet, P.D.; Medeiros, A.F.; Gobbi, D.; Wrasse, C.M.; Fechine, J.; Abdu, M.A.; Batista, I.S.; Paula, E.; et al. Simultaneous observation of ionospheric plasma bubbles and mesospheric gravity waves during the SpreadFEx Campaign. Ann. Geophys. 2009, 27, 1477–1487. [Google Scholar] [CrossRef] [Green Version]
- Terra, P.M.; Sobral, J.H.A.; Abdu, M.A.; Souza, J.R.; Takahashi, H. Plasma bubble zonal velocity variations with solar activity in the Brazilian region. Ann. Geophys. 2004, 22, 3123–3128. [Google Scholar] [CrossRef] [Green Version]
- Sobral, J.; Abdu, M.; Takahashi, H.; Taylor, M.; de Paula, E.; Zamlutti, C.; de Aquino, M.; Borba, G. Ionospheric plasma bubble climatology over Brazil based on 22 years (1977–1998) of 630nm airglow observations. J. Atmos. Sol.-Terr. Phys. 2002, 64, 1517–1524. [Google Scholar] [CrossRef]
- Taylor, M.J.; Eccles, J.V.; LaBelle, J.; Sobral, J.H.A. High resolution OI (630 nm) image measurements of F-region depletion drifts during the Guará Campaign. Geophys. Res. Lett. 1997, 24, 1699–1702. [Google Scholar] [CrossRef] [Green Version]
- Takahashi, H.; Wrasse, C.M.; Figueiredo, C.A.O.B.; Barros, D.; Abdu, M.A.; Otsuka, Y.; Shiokawa, K. Equatorial plasma bubble seeding by MSTIDs in the ionosphere. Prog. Earth Planet. Sci. 2018, 5, 32. [Google Scholar] [CrossRef] [Green Version]
- Schunk, R.; Nagy, A. Ionospheres: Physics, Plasma Physics, and Chemistry, 2nd ed.; Cambridge Atmospheric and Space Science Series; Cambridge University Press: Cambridge, UK, 2009. [Google Scholar] [CrossRef]
- Vargas, F. Traveling Ionosphere Disturbance Signatures on Ground-Based Observations of the O(1D) Nightglow Inferred From 1-D Modeling. J. Geophys. Res. Space Phys. 2019, 124, 9348–9363. [Google Scholar] [CrossRef]
- Medeiros, A.; Buriti, R.; Machado, E.; Takahashi, H.; Batista, P.; Gobbi, D.; Taylor, M. Comparison of gravity wave activity observed by airglow imaging at two different latitudes in Brazil. J. Atmos. Sol.-Terr. Phys. 2004, 66, 647–654. [Google Scholar] [CrossRef]
- Garcia, F.J.; Taylor, M.J.; Kelley, M.C. Two-dimensional spectral analysis of mesospheric airglow image data. Appl. Opt. 1997, 36, 7374–7385. [Google Scholar] [CrossRef] [PubMed] [Green Version]
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
Share and Cite
Vargas, F.; Brum, C.; Terra, P.; Gobbi, D. Mean Zonal Drift Velocities of Plasma Bubbles Estimated from Keograms of Nightglow All-Sky Images from the Brazilian Sector. Atmosphere 2020, 11, 69. https://doi.org/10.3390/atmos11010069
Vargas F, Brum C, Terra P, Gobbi D. Mean Zonal Drift Velocities of Plasma Bubbles Estimated from Keograms of Nightglow All-Sky Images from the Brazilian Sector. Atmosphere. 2020; 11(1):69. https://doi.org/10.3390/atmos11010069
Chicago/Turabian StyleVargas, Fabio, Christiano Brum, Pedrina Terra, and Delano Gobbi. 2020. "Mean Zonal Drift Velocities of Plasma Bubbles Estimated from Keograms of Nightglow All-Sky Images from the Brazilian Sector" Atmosphere 11, no. 1: 69. https://doi.org/10.3390/atmos11010069