Articles | Volume 25, issue 2
https://doi.org/10.5194/npg-25-477-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/npg-25-477-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
29 Jun 2018
Research article |
| 29 Jun 2018
| 29 Jun 2018
Preface: Nonlinear waves and chaos
Indian Institute of Geomagnetism, New Panvel (W), Navi Mumbai, India
Bruce T. Tsurutani
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
George J. Morales
Physics and Astronomy Department, University of California Los Angeles, Los Angeles, CA, USA
Annick Pouquet
UCAR, Boulder, CO, USA
Masahiro Hoshino
Department of Earth and Planetary Physics, University of Tokyo, Tokyo, Japan
Juan Alejandro Valdivia
Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
Yasuhito Narita
Austrian Academy of Sciences, Graz, Austria
Roger Grimshaw
Department of Mathematics, University College London, London, WC1E 6BT, UK
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Revealing the nature of Mercury’s internal magnetic field is one of the primary goals of the BepiColombo mission. Besides the parametrization of the magnetic field contributions, the application of a robust inversion method is of major importance. The present work provides an overview of the most commonly used inversion methods and shows that Capon’s method as well as the Tikhonov regularization enable a high-precision determination of Mercury’s internal magnetic field up to the fifth degree.
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Ann. Geophys., 39, 759–768, https://doi.org/10.5194/angeo-39-759-2021, https://doi.org/10.5194/angeo-39-759-2021, 2021
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The concept of electromotive force appears in various electromagnetic applications in geophysical and astrophysical fluid studies. The electromotive force is being recognized as a useful tool to construct a more complete picture of turbulent space plasma and has the potential to test for the fundamental processes of dynamo mechanism in space.
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Plasma waves are an integral part of cometary physics, as they facilitate the transfer of energy and momentum. From intermediate to strong activity, nonlinear asymmetric plasma and magnetic field enhancements dominate the inner coma of 67P/CG. We present a statistical survey of these structures from December 2014 to June 2016, facilitated by Rosetta's unprecedented long mission duration. Using a 1D MHD model, we show they can be described as a combination of nonlinear and dissipative effects.
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Identification of a large-amplitude Alfvén wave decaying into a pair of
ion-acoustic and daughter Alfvén waves is one of the major goals in the
observational studies of space plasma nonlinearity.
Growth-rate maps
may serve as a useful tool for predictions of the wavevector spectrum of density
or magnetic field fluctuations in various scenarios for the
wave–wave coupling processes developing at different stages in
space plasma turbulence.
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Yasuhito Narita, Wolfgang Baumjohann, and Rudolf A. Treumann
Ann. Geophys., 37, 825–834, https://doi.org/10.5194/angeo-37-825-2019, https://doi.org/10.5194/angeo-37-825-2019, 2019
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Scaling laws and energy spectra for the electric field, magnetic field, flow velocity, and density are theoretically derived for small-scale turbulence in space plasma on which the electrons behave as a fluid but the ions more as individual particles due to the difference in the mass (the Hall effect). Our theoretical model offers an explanation for the small-scale turbulence spectra measured in near-Earth space.
Anthony J. Mannucci, Ryan McGranaghan, Xing Meng, Bruce T. Tsurutani, and Olga P. Verkhoglyadova
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2019-108, https://doi.org/10.5194/angeo-2019-108, 2019
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Christoph Lhotka and Yasuhito Narita
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Rudolf A. Treumann, Wolfgang Baumjohann, and Yasuhito Narita
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Occasional deviations in density and magnetic power spectral densities in an intermediate frequency range are interpreted as an ion-inertial-range response to either the Kolmogorov or Iroshnikov–Kraichnan inertial-range turbulent velocity spectrum.
Kwok Wing Chow, Hiu Ning Chan, and Roger H. J. Grimshaw
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Oceanic rogue waves are unexpectedly large displacements from a tranquil background and pose dangers to shipping and offshore structures. A formulation of such abrupt, transient motions in the interior of the oceans is proposed. For constant buoyancy frequency, such internal rogue waves can occur in shallow fluids of various internal mode numbers, which is in strong contrast with surface rogue waves. Internal waves are crucial in oceanography as they affect transport of heat, mass and energy.
Ferdinand Plaschke, Hans-Ulrich Auster, David Fischer, Karl-Heinz Fornaçon, Werner Magnes, Ingo Richter, Dragos Constantinescu, and Yasuhito Narita
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Horia Comişel, Yasuhiro Nariyuki, Yasuhito Narita, and Uwe Motschmann
Ann. Geophys., 36, 1647–1655, https://doi.org/10.5194/angeo-36-1647-2018, https://doi.org/10.5194/angeo-36-1647-2018, 2018
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Space plasmas are assumed to be highly active and dynamic systems including waves and turbulence. Electromagnetic waves such as Alfven waves interact with one another, producing daughter waves. In our study based on three-dimensional hybrid simulations, we emphasize the role of obliquely propagating daughter waves in particle heating in low-temperature (or low-beta) plasmas. The evolutions of plasma turbulence, wave dissipation, and heating are essential problems in astrophysics.
Yasuhito Narita and Uwe Motschmann
Ann. Geophys., 36, 1537–1543, https://doi.org/10.5194/angeo-36-1537-2018, https://doi.org/10.5194/angeo-36-1537-2018, 2018
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Venus has no intrinsic magnetic field. On the other hand, we discover that an interplanetary magnetic field may nevertheless penetrate the planetary ionosphere by the diffusion process and reach the planetary surface when the solar wind condition remains for a sufficiently long time, between 12 and 54 h, depending on the condition of ionosphere.
Owen W. Roberts, Yasuhito Narita, and C.-Philippe Escoubet
Ann. Geophys., 36, 527–539, https://doi.org/10.5194/angeo-36-527-2018, https://doi.org/10.5194/angeo-36-527-2018, 2018
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In this study we use multi-point spacecraft measurements of magnetic field and electron density derived from spacecraft potential to investigate the three-dimensional structure of solar wind plasma turbulence. We see that there is a dependence on the plasma beta (ratio of thermal to magnetic pressure) as well as a dependence on the type of wind i.e. fast or slow.
Fernando L. Guarnieri, Bruce T. Tsurutani, Luis E. A. Vieira, Rajkumar Hajra, Ezequiel Echer, Anthony J. Mannucci, and Walter D. Gonzalez
Nonlin. Processes Geophys., 25, 67–76, https://doi.org/10.5194/npg-25-67-2018, https://doi.org/10.5194/npg-25-67-2018, 2018
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In this work we developed a method to obtain a time series named as AE* which is well correlated with the geomagnetic AE index. In this process, wavelet filtering is applied to interplanetary solar wind data from spacecrafts around the L1 libration point. This geomagnetic indicator AE* can be obtained well before the AE index release in its final form, and it can be used to feed models for geomagnetic effects, such as the relativistic electrons, giving forecasts ~ 1 to 2 days in advance.
Yasuhito Narita and Zoltán Vörös
Ann. Geophys., 36, 101–106, https://doi.org/10.5194/angeo-36-101-2018, https://doi.org/10.5194/angeo-36-101-2018, 2018
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Electromotive force plays a central role in the dynamo mechanism amplifying the magnetic field in turbulent plasmas and electrically conducting fluids. An algorithm is developed to measure the electromotive force using spacecraft data, and it is applied to a magnetic cloud event in interplanetary space. The electromotive force is enhanced when the magnetic cloud passes by the spacecraft, indicating local amplification of the magnetic field.
Owen W. Roberts, Yasuhito Narita, and C.-Philippe Escoubet
Ann. Geophys., 36, 47–52, https://doi.org/10.5194/angeo-36-47-2018, https://doi.org/10.5194/angeo-36-47-2018, 2018
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To investigate compressible plasma turbulence in the solar wind on proton kinetic scales, a high time resolution measurement of the density is obtained from the spacecraft potential. Correlation between the magnetic field strength and the density is investigated as is the rotation sense of the magnetic field. The analysis reveals that compressible fluctuations are characteristic of kinetic Alfvén waves or a mixture of kinetic Alfvén and kinetic slow waves which counter-propagate.
Gurbax S. Lakhina and Bruce T. Tsurutani
Nonlin. Processes Geophys., 24, 745–750, https://doi.org/10.5194/npg-24-745-2017, https://doi.org/10.5194/npg-24-745-2017, 2017
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A preliminary estimate of the drag force per unit mass on typical low-Earth-orbiting satellites moving through the ionosphere during Carrington-type super magnetic storms is calculated by a simple first-order model which takes into account the ion-neutral drag between the upward-moving oxygen ions and O neutral atoms. It is shown that oxygen ions and atoms can be uplifted to 850 km altitude, where they produce about 40 times more satellite drag per unit mass than normal.
Yasuhito Narita and Zoltán Vörös
Nonlin. Processes Geophys., 24, 673–679, https://doi.org/10.5194/npg-24-673-2017, https://doi.org/10.5194/npg-24-673-2017, 2017
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A method is proposed to determine the temporal decay rate of turbulent fluctuations, and is applied to four-point magnetic field data in interplanetary space. The measured decay, interpreted as the energy transfer rate in turbulence, is larger than the theoretical estimate from the fluid turbulence theory. The faster decay represents one of the differences in turbulent processes between fluid and plasma media.
Yasuhito Narita
Nonlin. Processes Geophys., 24, 203–214, https://doi.org/10.5194/npg-24-203-2017, https://doi.org/10.5194/npg-24-203-2017, 2017
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Various methods in the single-spacecraft data analysis are reviewed to determine physical properties of waves, turbulent fluctuations, and wave-wave and wave-particle interactions in the space plasma environment using the magnetic field, the electric field, and the plasma data.
Yasuhito Narita, Yoshihiro Nishimura, and Tohru Hada
Ann. Geophys., 35, 639–644, https://doi.org/10.5194/angeo-35-639-2017, https://doi.org/10.5194/angeo-35-639-2017, 2017
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An algorithm is proposed to estimate the spectral index of the turbulence energy spectrum directly in the wavenumber domain using multiple-sensor-array data. In contrast to the conventional method using time series data and Fourier transform of the fluctuation energy onto the frequency domain, the proposed algorithm does not require the assumption of Taylor's frozen inflow hypothesis, enabling direct comparison of the spectra in the wavenumber domain with various theoretical predictions.
Yasuhito Narita
Ann. Geophys., 35, 325–331, https://doi.org/10.5194/angeo-35-325-2017, https://doi.org/10.5194/angeo-35-325-2017, 2017
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In situ spacecraft data in space plasma are obtained often as time series data. Using Taylor's frozen-in flow hypothesis, one can interpret the time series data as spatial variations swept by the slow and passing by the spacecraft. A quantitative method for estimating the error for Taylor's hypothesis is developed here.
Martin Volwerk, Daniel Schmid, Bruce T. Tsurutani, Magda Delva, Ferdinand Plaschke, Yasuhito Narita, Tielong Zhang, and Karl-Heinz Glassmeier
Ann. Geophys., 34, 1099–1108, https://doi.org/10.5194/angeo-34-1099-2016, https://doi.org/10.5194/angeo-34-1099-2016, 2016
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The behaviour of mirror mode waves in Venus's magnetosheath is investigated for solar minimum and maximum conditions. It is shown that the total observational rate of these waves does not change much; however, the distribution over the magnetosheath is significantly different, as well as the growth and decay of the waves during these different solar activity conditions.
Horia Comişel, Yasuhiro Nariyuki, Yasuhito Narita, and Uwe Motschmann
Ann. Geophys., 34, 975–984, https://doi.org/10.5194/angeo-34-975-2016, https://doi.org/10.5194/angeo-34-975-2016, 2016
Ferdinand Plaschke and Yasuhito Narita
Ann. Geophys., 34, 759–766, https://doi.org/10.5194/angeo-34-759-2016, https://doi.org/10.5194/angeo-34-759-2016, 2016
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Spacecraft-mounted magnetic field instruments (magnetometers) need to be routinely calibrated. This involves determining the magnetometer outputs in vanishing ambient magnetic fields, the so-called offsets. We introduce and test a new method to determine these offsets with high accuracy, the mirror mode method, which is complementary to existing methods. The mirror mode method should be highly beneficial to current and future magnetic field observations near Earth, other planets, and comets.
Rudolf A. Treumann, Wolfgang Baumjohann, and Yasuhito Narita
Ann. Geophys., 34, 673–689, https://doi.org/10.5194/angeo-34-673-2016, https://doi.org/10.5194/angeo-34-673-2016, 2016
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In support of low-frequency electromagnetic turbulence we formulate the inverse scattering theory of electromagnetic fluctuations in plasma. Its solution provides the turbulent response function which contains all information of the dynamical causes of the electromagnetic fluctuations. This is of basic interest in any electromagnetic turbulence. It requires measurement of magnetic and electric fluctuations but makes no direct use of the turbulent power spectral density.
Ingo Richter, Hans-Ulrich Auster, Gerhard Berghofer, Chris Carr, Emanuele Cupido, Karl-Heinz Fornaçon, Charlotte Goetz, Philip Heinisch, Christoph Koenders, Bernd Stoll, Bruce T. Tsurutani, Claire Vallat, Martin Volwerk, and Karl-Heinz Glassmeier
Ann. Geophys., 34, 609–622, https://doi.org/10.5194/angeo-34-609-2016, https://doi.org/10.5194/angeo-34-609-2016, 2016
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We have analysed the magnetic field measurements performed on the ROSETTA orbiter and the lander PHILAE during PHILAE's descent to comet 67P/Churyumov-Gerasimenko on 12 November 2014. We observed a new type of low-frequency wave with amplitudes of ~ 3 nT, frequencies of 20–50 mHz, wavelengths of ~ 300 km, and propagation velocities of ~ 6 km s−1. The waves are generated in a ~ 100 km region around the comet a show a highly correlated behaviour, which could only be determined by two-point observations.
Y. Narita, H. Comişel, and U. Motschmann
Ann. Geophys., 34, 591–593, https://doi.org/10.5194/angeo-34-591-2016, https://doi.org/10.5194/angeo-34-591-2016, 2016
Y. Narita, E. Marsch, C. Perschke, K.-H. Glassmeier, U. Motschmann, and H. Comişel
Ann. Geophys., 34, 393–398, https://doi.org/10.5194/angeo-34-393-2016, https://doi.org/10.5194/angeo-34-393-2016, 2016
Y. Narita, R. Nakamura, W. Baumjohann, K.-H. Glassmeier, U. Motschmann, and H. Comişel
Ann. Geophys., 34, 85–89, https://doi.org/10.5194/angeo-34-85-2016, https://doi.org/10.5194/angeo-34-85-2016, 2016
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Four-spacecraft Cluster observations of turbulent fluctuations in the magnetic reconnection region in the geomagnetic tail show for the first time an indication of ion Bernstein waves, electromagnetic waves that propagate nearly perpendicular to the mean magnetic field and are in resonance with ions. Bernstein waves may influence current sheet dynamics in the reconnection outflow such as a bifurcation of the current sheet.
M. Volwerk, I. Richter, B. Tsurutani, C. Götz, K. Altwegg, T. Broiles, J. Burch, C. Carr, E. Cupido, M. Delva, M. Dósa, N. J. T. Edberg, A. Eriksson, P. Henri, C. Koenders, J.-P. Lebreton, K. E. Mandt, H. Nilsson, A. Opitz, M. Rubin, K. Schwingenschuh, G. Stenberg Wieser, K. Szegö, C. Vallat, X. Vallieres, and K.-H. Glassmeier
Ann. Geophys., 34, 1–15, https://doi.org/10.5194/angeo-34-1-2016, https://doi.org/10.5194/angeo-34-1-2016, 2016
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The solar wind magnetic field drapes around the active nucleus of comet 67P/CG, creating a magnetosphere. The solar wind density increases and with that the pressure, which compresses the magnetosphere, increasing the magnetic field strength near Rosetta. The higher solar wind density also creates more ionization through collisions with the gas from the comet. The new ions are picked-up by the magnetic field and generate mirror-mode waves, creating low-field high-density "bottles" near 67P/CG.
Y. Narita
Ann. Geophys., 33, 1413–1419, https://doi.org/10.5194/angeo-33-1413-2015, https://doi.org/10.5194/angeo-33-1413-2015, 2015
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A lot of efforts have been put into understanding the turbulence structure in space and astrophysical plasmas, in particular how the filamentary structure develops as the length scale of the turbulent fluctuations changes from large to smaller ones. Motivated by the recent spacecraft observations in the solar wind, an analytic model is proposed to explain the nature of filament-formation processes in space plasma turbulence with a successful test against the spacecraft observations.
I. Richter, C. Koenders, H.-U. Auster, D. Frühauff, C. Götz, P. Heinisch, C. Perschke, U. Motschmann, B. Stoll, K. Altwegg, J. Burch, C. Carr, E. Cupido, A. Eriksson, P. Henri, R. Goldstein, J.-P. Lebreton, P. Mokashi, Z. Nemeth, H. Nilsson, M. Rubin, K. Szegö, B. T. Tsurutani, C. Vallat, M. Volwerk, and K.-H. Glassmeier
Ann. Geophys., 33, 1031–1036, https://doi.org/10.5194/angeo-33-1031-2015, https://doi.org/10.5194/angeo-33-1031-2015, 2015
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We present a first report on magnetic field measurements made in the coma of comet 67P/C-G in its low-activity state. The plasma environment is dominated by quasi-coherent, large-amplitude, compressional magnetic field oscillations around 40mHz, differing from the observations at strongly active comets where waves at the cometary ion gyro-frequencies are the main feature. We propose a cross-field current instability associated with the newborn cometary ions as a possible source mechanism.
B. T. Tsurutani, R. Hajra, E. Echer, and J. W. Gjerloev
Ann. Geophys., 33, 519–524, https://doi.org/10.5194/angeo-33-519-2015, https://doi.org/10.5194/angeo-33-519-2015, 2015
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Particularly intense substorms (SSS), brilliant auroral displays with strong >106A currents in the ionosphere, are studied. It is believed that these SSS events cause power outages during magnetic storms. It is shown that SSS events can occur during all intensity magnetic storms; thus power problems are not necessarily restricted to the rare most intense storms. We show four SSS events that are triggered by solar wind pressure pulses. If this is typical, ~30-minute warnings could be issued.
J. Wanliss, V. Muñoz, D. Pastén, B. Toledo, and J. A. Valdivia
Nonlin. Processes Geophys. Discuss., https://doi.org/10.5194/npgd-2-619-2015, https://doi.org/10.5194/npgd-2-619-2015, 2015
Revised manuscript not accepted
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We explore bursty multiscale energy dissipation from earthquakes by comparing predictions of nonequilibrium phase transitions with nonstandard statistical signatures of earthquake scaling. Do earthquakes fit the hypothesis of an avalanching critical system? We study a set of new power law exponents, and compare these explicitly to predictions for critical avalanching systems. At below 84 hours radiated energy follows patterns fitting the theory of nonequilibrium phase transitions.
H. Comişel, Y. Narita, and U. Motschmann
Ann. Geophys., 33, 345–350, https://doi.org/10.5194/angeo-33-345-2015, https://doi.org/10.5194/angeo-33-345-2015, 2015
H. Comişel, Y. Narita, and U. Motschmann
Nonlin. Processes Geophys., 21, 1075–1083, https://doi.org/10.5194/npg-21-1075-2014, https://doi.org/10.5194/npg-21-1075-2014, 2014
D. Schmid, M. Volwerk, F. Plaschke, Z. Vörös, T. L. Zhang, W. Baumjohann, and Y. Narita
Ann. Geophys., 32, 651–657, https://doi.org/10.5194/angeo-32-651-2014, https://doi.org/10.5194/angeo-32-651-2014, 2014
M. Wilczek, H. Xu, and Y. Narita
Nonlin. Processes Geophys., 21, 645–649, https://doi.org/10.5194/npg-21-645-2014, https://doi.org/10.5194/npg-21-645-2014, 2014
Y. Narita
Nonlin. Processes Geophys., 21, 41–47, https://doi.org/10.5194/npg-21-41-2014, https://doi.org/10.5194/npg-21-41-2014, 2014
C. Perschke, Y. Narita, S. P. Gary, U. Motschmann, and K.-H. Glassmeier
Ann. Geophys., 31, 1949–1955, https://doi.org/10.5194/angeo-31-1949-2013, https://doi.org/10.5194/angeo-31-1949-2013, 2013
Y. Narita, R. Nakamura, and W. Baumjohann
Ann. Geophys., 31, 1605–1610, https://doi.org/10.5194/angeo-31-1605-2013, https://doi.org/10.5194/angeo-31-1605-2013, 2013
B. T. Tsurutani, A. J. Mannuccci, O. P. Verkhoglyadova, and G. S. Lakhina
Ann. Geophys., 31, 145–150, https://doi.org/10.5194/angeo-31-145-2013, https://doi.org/10.5194/angeo-31-145-2013, 2013
Cited articles
Faranda, D., Messori, G., Alvarez-Castro, M. C., and Yiou, P.: Dynamical
properties and extremes of Northern Hemisphere climate fields over the past
60 years, Nonlin. Processes Geophys., 24, 713–725,
https://doi.org/10.5194/npg-24-713-2017, 2017.
Guarnieri, F. L., Tsurutani, B. T., Vieira, L. E. A., Hajra, R., Echer, E.,
Mannucci, A. J., and Gonzalez, W. D.: A correlation study regarding the AE
index and ACE solar wind data for Alfvénic intervals using wavelet
decomposition and reconstruction, Nonlin. Processes Geophys., 25, 67–76,
https://doi.org/10.5194/npg-25-67-2018, 2018.
Lakhina, G. S. and Tsurutani, B. T.: Satellite drag effects due to uplifted
oxygen neutrals during super magnetic storms, Nonlin. Processes Geophys., 24,
745–750, https://doi.org/10.5194/npg-24-745-2017, 2017.
Livadiotis, G.: Derivation of the entropic formula for the statistical
mechanics of space plasmas, Nonlin. Processes Geophys., 25, 77–88,
https://doi.org/10.5194/npg-25-77-2018, 2018.
Macek, W. M., Wawrzaszek, A., and Kucharuk, B.: Intermittent turbulence in
the heliosheath and the magnetosheath plasmas based on Voyager and THEMIS
data, Nonlin. Processes Geophys., 25, 39–54,
https://doi.org/10.5194/npg-25-39-2018, 2018.
Muñoz, V., Domínguez, M., Valdivia, J. A., Good, S., Nigro, G., and
Carbone, V.: Evolution of fractality in space plasmas of interest to
geomagnetic activity, Nonlin. Processes Geophys., 25, 207–216,
https://doi.org/10.5194/npg-25-207-2018, 2018.
Narita, Y. and Vörös, Z.: Lifetime estimate for plasma turbulence,
Nonlin. Processes Geophys., 24, 673–679,
https://doi.org/10.5194/npg-24-673-2017, 2017.
