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145 results on '"Verkhoglyadova, O. P"'

1. Impact of Space Weather on Climate and Habitability of Terrestrial Type Exoplanets

Author

Airapetian, V. S., Barnes, R., Cohen, O., Collinson, G. A., Danchi, W. C., Dong, C. F., Del Genio, A. D., France, K., Garcia-Sage, K., Glocer, A., Gopalswamy, N., Grenfell, J. L., Gronoff, G., G"udel, M., Herbst, K., Henning, W. G., Jackman, C. H., Jin, M., Johnstone, C. P., Kaltenegger, L., Kay, C. D., Kobayashi, K., Kuang, W., Li, G., Lynch, B. J., L"uftinger, T., Luhmann, TJ. G., Maehara, H., Mlynczak, M. G., Notsu, Y., Ramirez, R. M., Rugheimer, S., Scheucher, M., Schlieder, J. E., Shibata, K., Sousa-Silva, C., Stamenkovi'c, V., Strangeway, R. J., Usmanov, A. V., Vergados, P., Verkhoglyadova, O. P., Vidotto, A. A., Voytek, M., Way, M. J., Zank, G. P., and Yamashiki, Y.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

The current progress in the detection of terrestrial type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favorable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of astrospheric, atmospheric and surface environments of exoplanets in habitable zones around G-K-M dwarfs including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles, and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favorable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro) physical, chemical, and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the habitable zone to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology., Comment: 206 pages, 24 figures, 1 table; Review paper. International Journal of Astrobiology (2019)

Published
2019
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2. Life Beyond the Solar System: Space Weather and Its Impact on Habitable Worlds

Author

Airapetian, V. S., Danchi, W. C., Dong, C. F., Rugheimer, S., Mlynczak, M., Stevenson, K. B., Henning, W. G., Grenfell, J. L., Jin, M., Glocer, A., Gronoff, G., Lynch, B., Johnstone, C., Lueftinger, T., Guedel, M., Kobayashi, K., Fahrenbach, A., Hallinan, G., Stamenkovic, V., Cohen, O., Kuang, W., van der Holst, B., Manchester, C., Zank, G., Verkhoglyadova, O., Sojka, J., Maehara, H., Notsu, Y., Yamashiki, Y., France, K., Puertas, M. Lopez, Funke, B., Jackman, C., Kay, C., Leisawitz, D., and Alexander, D.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

The search of life in the Universe is a fundamental problem of astrobiology and a major priority for NASA. A key area of major progress since the NASA Astrobiology Strategy 2015 (NAS15) has been a shift from the exoplanet discovery phase to a phase of characterization and modeling of the physics and chemistry of exoplanetary atmospheres, and the development of observational strategies for the search for life in the Universe by combining expertise from four NASA science disciplines including heliophysics, astrophysics, planetary science and Earth science. The NASA Nexus for Exoplanetary System Science (NExSS) has provided an efficient environment for such interdisciplinary studies. Solar flares, coronal mass ejections and solar energetic particles produce disturbances in interplanetary space collectively referred to as space weather, which interacts with the Earth upper atmosphere and causes dramatic impact on space and ground-based technological systems. Exoplanets within close in habitable zones around M dwarfs and other active stars are exposed to extreme ionizing radiation fluxes, thus making exoplanetary space weather (ESW) effects a crucial factor of habitability. In this paper, we describe the recent developments and provide recommendations in this interdisciplinary effort with the focus on the impacts of ESW on habitability, and the prospects for future progress in searching for signs of life in the Universe as the outcome of the NExSS workshop held in Nov 29 - Dec 2, 2016, New Orleans, LA. This is one of five Life Beyond the Solar System white papers submitted by NExSS to the National Academy of Sciences in support of the Astrobiology Science Strategy for the Search for Life in the Universe., Comment: 5 pages, the white paper was submitted to the National Academy of Sciences in support of the Astrobiology Science Strategy for the Search for Life in the Universe

Published
2018

3. Understanding the Transfer of Electromagnetic Energy Between the Earth’s Magnetosphere and Upper Atmosphere

Author

Chartier, Alex, primary, Matsuo, T., additional, Perry, G. W., additional, Deng, Y., additional, Billett, D., additional, Cosgrove, R. B., additional, Thayer, J. P., additional, Lu, G., additional, Verkhoglyadova, O. P., additional, Pfaff, R. F., additional, Knipp, D. J., additional, Laakso, H. E., additional, Datta-Barua, S., additional, and Vines, S. K., additional

Published
2023
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4. Statistical Characteristics of Total Electron Content Intensifications on Global Ionospheric Maps.

Author

Meng, X., Verkhoglyadova, O. P., Chapman, S. C., Watkins, N. W., and Cafolla, M.

Subjects
FEATURE extraction, SOLAR cycle, IMAGE processing software, SPACE environment, ATMOSPHERIC layers, ELECTRONS, GEOMAGNETISM
Abstract

Global ionospheric total electron content (TEC) maps exhibit TEC intensifications and depletions of various sizes and shapes. Characterizing key features on TEC maps and understanding their dynamic coupling with external drivers can significantly benefit space weather forecasting. However, comprehensive analysis of ionospheric structuring over decades of TEC maps is currently lacking due to large data volume. We develop feature extraction software based on image processing techniques to extract TEC intensification regions, that is, contiguous regions with sufficiently elevated TEC values than surrounding areas, from global TEC maps. Applying the software to the Jet Propulsion Laboratory Global Ionospheric Map data, we generate a TEC intensification data set for years 2003–2022 and carry out a statistical study on the number and strength of TEC intensifications. We find that the majority of the TEC maps (about 86%) are characterized with one or two intensification(s), while the rest of the TEC maps have three or more intensifications. Both the number and strength of TEC intensifications exhibit semi‐annual variation that peaks near equinoxes and dips near solstices, as well as an annual asymmetry with larger values around December solstice compared to June solstice. The number and strength of intensifications increase with enhanced solar extreme‐violet irradiance. The strength of intensifications also increases with elevated geomagnetic activity, but the number of intensifications does not. In addition, the number of intensifications is not correlated with the strength of intensifications. Plain Language Summary: The ionosphere is an upper atmospheric layer containing free electrons and ions. The abundance of ionospheric electrons varies from one location to another, creating electron intensification and depletion regions of various sizes and shapes. We develop feature extraction software to identify the electron intensification regions from two‐dimensional electron abundance maps and generate a data set of their strengths and locations over two decades. We conduct a statistical study of the data set and find that most maps are with one or two intensification region(s). Maps with three or more intensification regions also occur. The number of intensification regions on a TEC map is modulated by season and solar irradiance. The strength of intensification regions is modulated by season, solar irradiance, and solar activity. Our result advances the knowledge on global ionosphere structuring, which is critical for space‐borne navigation and communication. Key Points: Feature extraction software is applied to generate a total electron content (TEC) intensification data set from global TEC maps spanning 20 yearsOne or two intensification(s) are identified for 86% of the TEC maps, while rest of the TEC maps have three or more intensificationsThe occurrence and strength of TEC intensifications vary with season and solar cycle, and the strength varies with geomagnetic activity [ABSTRACT FROM AUTHOR]

Published
2024
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18. Modeling of Ionospheric Responses to Atmospheric Acoustic and Gravity Waves Driven by the 2015 Nepal M w 7.8 Gorkha Earthquake

Author

2417495, 1670664, 1570197, Inchin, P. A., Snively, J. B., Zettergren, M. D., Komjathy, A., Verkhoglyadova, O. P., Ram, S. Tulasi, 2417495, 1670664, 1570197, Inchin, P. A., Snively, J. B., Zettergren, M. D., Komjathy, A., Verkhoglyadova, O. P., and Ram, S. Tulasi

Abstract

Near- and far-field ionospheric responses to atmospheric acoustic and gravity waves (AGWs) generated by surface displacements during the 2015 Nepal 7.8 Gorkha earthquake are simulated. Realistic surface displacements driven by the earthquake are calculated in three-dimensional forward seismic waves propagation simulation, based on kinematic slip model. They are used to excite AGWs at ground level in the direct numerical simulation of three-dimensional nonlinear compressible Navier-Stokes equations with neutral atmosphere model, which is coupled with a two-dimensional nonlinear multifluid electrodynamic ionospheric model. The importance of incorporating earthquake rupture kinematics for the simulation of realistic coseismic ionospheric disturbances (CIDs) is demonstrated and the possibility of describing faulting mechanisms and surface deformations based on ionospheric observations is discussed in details. Simulation results at the near-epicentral region are comparable with total electron content (TEC) observations in periods ( 3.3 and 6-10 min for acoustic and gravity waves, respectively), propagation velocities ( 0.92 km/s for acoustic waves) and amplitudes (up to 2 TECu). Simulated far-field CIDs correspond to long-period ( 4 mHz) Rayleigh waves (RWs), propagating with the same phase velocity of 4 km/s. The characteristics of modeled RW-related ionospheric disturbances differ from previously-reported observations based on TEC data; possible reasons for these differences are discussed.

Published
2020

24. Impact of space weather on climate and habitability of terrestrial-type exoplanets

Author

Airapetian, V. S., primary, Barnes, R., additional, Cohen, O., additional, Collinson, G. A., additional, Danchi, W. C., additional, Dong, C. F., additional, Del Genio, A. D., additional, France, K., additional, Garcia-Sage, K., additional, Glocer, A., additional, Gopalswamy, N., additional, Grenfell, J. L., additional, Gronoff, G., additional, Güdel, M., additional, Herbst, K., additional, Henning, W. G., additional, Jackman, C. H., additional, Jin, M., additional, Johnstone, C. P., additional, Kaltenegger, L., additional, Kay, C. D., additional, Kobayashi, K., additional, Kuang, W., additional, Li, G., additional, Lynch, B. J., additional, Lüftinger, T., additional, Luhmann, J. G., additional, Maehara, H., additional, Mlynczak, M. G., additional, Notsu, Y., additional, Osten, R. A., additional, Ramirez, R. M., additional, Rugheimer, S., additional, Scheucher, M., additional, Schlieder, J. E., additional, Shibata, K., additional, Sousa-Silva, C., additional, Stamenković, V., additional, Strangeway, R. J., additional, Usmanov, A. V., additional, Vergados, P., additional, Verkhoglyadova, O. P., additional, Vidotto, A. A., additional, Voytek, M., additional, Way, M. J., additional, Zank, G. P., additional, and Yamashiki, Y., additional

Published
2019
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25. Plasma-beam instabilities in cometary ionospheres

Author

Churyumov, Klim I, Kotsarenko, N. YA, Lizunov, G. V, and Verkhoglyadova, O. P

Subjects
Astrophysics
Abstract

It is shown that the interaction between the solar wind flux and the cometary ionosphere leads to the excitation of ion sound, whistler, electron-cyclotron, low hybrid, and magnetohydrodynamic waves. We investigated the frequency spectrum and found linear-increasing increments and lengths of excited waves.

Published
1992

26. Modeling of Ionospheric Responses to Atmospheric Acoustic and Gravity Waves Driven by the 2015 Nepal Mw7.8 Gorkha Earthquake.

Author

Inchin, P. A., Snively, J. B., Zettergren, M. D., Komjathy, A., Verkhoglyadova, O. P., and Tulasi Ram, S.

Subjects
IONOSPHERIC disturbances, GRAVITATIONAL waves, NEPAL Earthquake, 2015, SEISMIC wave velocity, FREQUENCY response
Abstract

Near‐ and far‐field ionospheric responses to atmospheric acoustic and gravity waves (AGWs) generated by surface displacements during the 2015 Nepal Mw7.8 Gorkha earthquake are simulated. Realistic surface displacements driven by the earthquake are calculated in three‐dimensional forward seismic waves propagation simulation, based on kinematic slip model. They are used to excite AGWs at ground level in the direct numerical simulation of three‐dimensional nonlinear compressible Navier‐Stokes equations with neutral atmosphere model, which is coupled with a two‐dimensional nonlinear multifluid electrodynamic ionospheric model. The importance of incorporating earthquake rupture kinematics for the simulation of realistic coseismic ionospheric disturbances (CIDs) is demonstrated and the possibility of describing faulting mechanisms and surface deformations based on ionospheric observations is discussed in details. Simulation results at the near‐epicentral region are comparable with total electron content (TEC) observations in periods (∼3.3 and ∼6‐10 min for acoustic and gravity waves, respectively), propagation velocities (∼0.92 km/s for acoustic waves) and amplitudes (up to ∼2 TECu). Simulated far‐field CIDs correspond to long‐period (∼4 mHz) Rayleigh waves (RWs), propagating with the same phase velocity of ∼4 km/s. The characteristics of modeled RW‐related ionospheric disturbances differ from previously‐reported observations based on TEC data; possible reasons for these differences are discussed. Key Points: Seismically generated AGW dynamics from ground to exobase are simulated based on realistic spatial and temporal surface displacementsSimulation results of near‐epicentral ionospheric responses to AGWs are consistent with observations in amplitudes, periods, and speedsResults identify challenges and opportunities for faulting mechanism characterization based on ionospheric observations [ABSTRACT FROM AUTHOR]

Published
2020
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29. Nonlinear Ionospheric Responses to Large-Amplitude Infrasonic-Acoustic Waves Generated by Undersea Earthquakes

Author

1670664, Zettergren, M. D., Snively, J. B., Komjathy, A., Verkhoglyadova, O. P., 1670664, Zettergren, M. D., Snively, J. B., Komjathy, A., and Verkhoglyadova, O. P.

Abstract

Numerical models of ionospheric coupling with the neutral atmosphere are used to investigate perturbations of plasma density, vertically integrated total electron content (TEC), neutral velocity, and neutral temperature associated with large-amplitude acoustic waves generated by the initial ocean surface displacements from strong undersea earthquakes. A simplified source model for the 2011 Tohoku earthquake is constructed from estimates of initial ocean surface responses to approximate the vertical motions over realistic spatial and temporal scales. Resulting TEC perturbations from modeling case studies appear consistent with observational data, reproducing pronounced TEC depletions which are shown to be a consequence of the impacts of nonlinear, dissipating acoustic waves. Thermospheric acoustic compressional velocities are ∼±250–300 m/s, superposed with downward flows of similar amplitudes, and temperature perturbations are ∼300 K, while the dominant wave periodicity in the thermosphere is ∼3–4 min. Results capture acoustic wave processes including reflection, onset of resonance, and nonlinear steepening and dissipation—ultimately leading to the formation of ionospheric TEC depletions “holes”—that are consistent with reported observations. Three additional simulations illustrate the dependence of atmospheric acoustic wave and subsequent ionospheric responses on the surface displacement amplitude, which is varied from the Tohoku case study by factors of 1/100, 1/10, and 2. Collectively, results suggest that TEC depletions may only accompany very-large amplitude thermospheric acoustic waves necessary to induce a nonlinear response, here with saturated compressional velocities∼200–250 m/s generated by sea surface displacements exceeding ∼ 1 m occurring over a 3 min time period.

Published
2017

35. Understanding large SEP events with the PATH code: Modeling of the 13 December 2006 SEP event

Author

Verkhoglyadova, O. P., Li, G., Zank, G. P., Hu, Q., Cohen, C. M. S., Mewaldt, R. A., Mason, G. M., Haggerty, D. K., von Rosenvinge, T. T., and Looper, M. D.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics
Abstract

The Particle Acceleration and Transport in the Heliosphere (PATH) numerical code was developed to understand solar energetic particle (SEP) events in the near-Earth environment. We discuss simulation results for the 13 December 2006 SEP event. The PATH code includes modeling a background solar wind through which a CME-driven oblique shock propagates. The code incorporates a mixed population of both flare and shock-accelerated solar wind suprathermal particles. The shock parameters derived from ACE measurements at 1 AU and observational flare characteristics are used as input into the numerical model. We assume that the diffusive shock acceleration mechanism is responsible for particle energization. We model the subsequent transport of particles originated at the flare site and particles escaping from the shock and propagating in the equatorial plane through the interplanetary medium. We derive spectra for protons, oxygen, and iron ions, together with their time-intensity profiles at 1 AU. Our modeling results show reasonable agreement with in situ measurements by ACE, STEREO, GOES, and SAMPEX for this event. We numerically estimate the Fe/O abundance ratio and discuss the physics underlying a mixed SEP event. We point out that the flare population is as important as shock geometry changes during shock propagation for modeling time-intensity profiles and spectra at 1 AU. The combined effects of seed population and shock geometry will be examined in the framework of an extended PATH code in future modeling efforts.

Published
2010

39. Medium-Range Thermosphere-Ionosphere Storm Forecasts

Author

Mannucci, A. J., primary, Verkhoglyadova, O. P., additional, Tsurutani, B. T., additional, Meng, X., additional, Pi, X., additional, Wang, C., additional, Rosen, G., additional, Lynch, E., additional, Sharma, S., additional, Ridley, A., additional, Manchester, W., additional, Van Der Holst, B., additional, Echer, E., additional, and Hajra, R., additional

Published
2015
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42. Wave vector directions of whistler-mode chorus

Author

Santolík, O., Pickett, J. S., Gurnett, D. A., Macusova, E., Menietti, J. D., Cornilleau-Wehrlin, Nicole, Tsurutani, B. T., Verkhoglyadova, O. P., Laboratoire de Physique des Plasmas (LPP), Université Paris-Saclay-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École polytechnique (X)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)

Subjects
[PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics
Abstract

International audience; Whistler-mode chorus has been shown to play a significant role in acceleration of relativistic electrons in the outer Van Allen radiation belt. It can also propagate from its source region and influence large regions of the inner magnetosphere. Distribution of the wave energy density in the space of the wave vector directions is a crucial parameter for modeling of both the wave-particle interactions and wave propagation in the inner magnetosphere. We present a survey of observations of whistler-mode chorus emissions by the Plasma Wave Instrument on the Polar spacecraft in 1996 and 1997 together with a large data set obtained by the STAFF-SA instruments onboard the CLUSTER spacecraft. We show that highly oblique propagation needs to be considered in the radiation belt models.

Published
2009

46. The Dayside Ionospheric Superfountain Effect, Plasma Transport and Other Implied Consequences

Author

Sobral, Jose Humberto Andrade, Tsurutani, B. T., Saito, A., Verkhoglyadova, O. P., Mannucci, A. J., Araki, T., Fuller-Rowell, T., Gonzalez-Alarcon, Walter Demetrio, Iijima, B. A., Lakhina, G. S., Maccreadie, H., Sobral, Jose Humberto Andrade, Tsurutani, B. T., Saito, A., Verkhoglyadova, O. P., Mannucci, A. J., Araki, T., Fuller-Rowell, T., Gonzalez-Alarcon, Walter Demetrio, Iijima, B. A., Lakhina, G. S., and Maccreadie, H.

Abstract

Pages: prelo

Published
2007

47. The Dayside ionospheric 'Superfountain' (DIS), plasma transport and other consequences

Author

Tsurutani, B. T., Saito, A., Verkhoglyadova, O. P., Mannucci, A. J., Abdu, Mangalathayil Ali, Araki, T., Gonzalez-Alarcon, Walter Demétrio, Iijima, B. A., Lakhina, G. S., McCreadie, H., Sobral, José Humberto Andrade, Tsuda, T., Yumoto, K., Vasyliunas, V. M., Tsurutani, B. T., Saito, A., Verkhoglyadova, O. P., Mannucci, A. J., Abdu, Mangalathayil Ali, Araki, T., Gonzalez-Alarcon, Walter Demétrio, Iijima, B. A., Lakhina, G. S., McCreadie, H., Sobral, José Humberto Andrade, Tsuda, T., Yumoto, K., and Vasyliunas, V. M.

Abstract

Prompt penetration electric fields (PPEFs) and the consequential dayside ionospheric superfountain (DIS) are reviewed. An example of O+ uplift to ~840 km altitude at ~0940 local time (DMSP F15) during the superstorm of 30 October 2003 is illustrated. The SAMI-2 model is modified to incorporate intense superstorm electric fields. With an inclusion of a ~4 mV/m eastward electric field, SAMI-2* modeling results show many of the expected DIS effects., isbn: 81-87099-40-2, Pages: 384-388

Published
2006

48. Dayside ionospheric (GPS) response to corotating solar wind streams

Author

Tsurutani, B. T., Mannucci, A. J., Iijima, B. A., Komjathy, A., Saito, A., Tsuda, T., Verkhoglyadova, O. P., Gonzalez Alarcon, Walter Demétrio, Guarnieri, Fernando Luis, Tsurutani, B. T., Mannucci, A. J., Iijima, B. A., Komjathy, A., Saito, A., Tsuda, T., Verkhoglyadova, O. P., Gonzalez Alarcon, Walter Demétrio, and Guarnieri, Fernando Luis

Abstract

The dayside ionospheric modifications associated with the three phases of corotating stream-generated magnetic storms (initial, main and recovery) are investigated. The high density heliospheric current sheet plasmasheet (HCSPS) pressure pulse impingements onto the magnetosphere, the collision of high magnetic field intensity corotating interaction regions (CIRs) onto the magnetosphere, and high speed stream Alfvénic interval ionospheric effects are all investigated using both GPS ground and satellite receiver data. The above results are compared with results associated with magnetic storms caused by interplanetary coronal mass ejections (ICMEs). The main effect found is that southward GSM Bz magnetic fields within CIRs cause an uplift of the dayside ionosphere with the consequence of enhanced ionospheric total electron content (TEC). This limited dayside effect is believed to be due to the variable magnetic field z-components within CIRs. Global dayside and nightside auroral zone ionospheric TEC enhancements are noted associated with the high solar wind Alfvénic intervals. Interpretation of our findings will be given, plus directions for future research in this new and emerging area of space weather., isbn: 978-0-87590-432-0, Pages: 245-270

Published
2006

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