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Mapping Local Singularities Using Magnetic Data to Investigate the...

By: Q. Cheng; T. Liu; Y. Yang; G. Chen

Description: State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, 430074, China. The spatial structural characteristics of geological anomaly, including singularity and self-similarity, can be analysed using fractal or multifractal modelling. Here we apply the multifractal methods to potential fields to demonstrate that singularities can characterise geological bodies, including rock density and magnetic suscepti...

Agterberg, F. P.: Multifractals and geostatistics, J. Geochem. Explor., 122, 113–122, doi:10.1016/j.gexplo.2012.04.001, 2012.; Benzi, R., Paladin, G., Parisi, G., and Vulpiani, A.: On the multifractal nature of fully developed turbulence and chaotic systems, J. Phys. A-Math. Gen., 17, 3521, doi:10.1088/0305-4470/17/18/021, 1984.; Chen, J. G., Xiao, F., and...

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On the Multi-scale Nature of Large Geomagnetic Storms: an Empirica...

By: R. Tozzi; G. Consolini; P. De Michelis

Description: Istituto Nazionale di Geofisica e Vulcanologia, 00143 Roma, Italy. Complexity and multi-scale are very common properties of several geomagnetic time series. On the other hand, it is amply demonstrated that scaling properties of geomagnetic time series show significant changes depending on the geomagnetic activity level. Here, we study the multi-scale features of some large geomagnetic storms by applying the empirical mode decomposition technique. This m...

Kamide, Y.: Is substorm occurrence a necessary condition for a magnetic storm?, J. Geomagn. Geoelectr., 44, 109–117, 1992.; Chang, T., Tam, S. W. Y., Wu, C. C., and Consolini, G.: Complexity, forced and/or self-organized criticality, and topological phase transitions in space plasmas, Space Sci. Rev., 107, 425–445, 2003.; Chapman, S. C. and Watkins, N. W.: Avalanching and self organised criticality: a paradigm for magnetospheric dynamics?, Space Sci. Rev., 95, 293–307, 2...

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Universal Multifractal Martian Topography : Volume 2, Issue 4 (18/...

By: S. Lovejoy; F. Schmidt; F. Landais

Description: Univ Paris-Sud, Laboratoire GEOPS, UMR8148, Orsay, 91405. In the present study, we investigate the scaling properties of the topography of Mars. Planetary topographic fields are well known to roughly exhibit (mono)fractal behavior. Indeed, the fractal formalism is reproduces much of the variability observed in topography. Still, a single fractal dimension is not enough to explain the huge variability and intermittency. Previous studies have claimed that...

Aharonson, O., Zuber, M. T., and Rothman, D. H.: Statistics of Mars' topography from the Mars orbiter laser altimeter: slopes, correlations, and physical Models, J. Geophys. Res.-Planet., 106, 23723–23735, doi:10.1029/2000JE001403, 2001.; Baldassarri, A., Montuori, M., Prieto-Ballesteros, O., and Manrubia, S. C.: Fractal properties of isolines at varying altitude revealing different dominant geological processes on Earth...

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Estimation of the Local Response to a Forcing in a High Dimensiona...

By: P. H. Haynes; J. G. Esler; F. C. Cooper

Description: Atmospheric, Oceanic and Planetary Physics, University of Oxford, Oxford, UK. The fluctuation-dissipation theorem (FDT) has been proposed as a method of calculating the response of the earth's atmosphere to a forcing. For this problem the high dimensionality of the relevant data sets makes truncation necessary. Here we propose a method of truncation based upon the assumption that the response to a localised forcing is spatially localised, as an alternat...

Abramov, R. V. and Majda, A. J.: Blended response algorithms for linear fluctuation-dissipation for complex nonlinear dynamical systems, Nonlinearity, 20, 2793–2821, doi:10.1088/0951-7715/20/12/004, 2007.; Boffetta, G., Lacorata, G., Musacchio, S., and Vulpiani, A.: Relaxation of finite perturbations: Beyond the fluctuation-response relation, Chaos, 13, 806–811, doi:10.1...

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Particle Dispersion Processes in Two-dimensional Turbulence: a Com...

By: J. M. Redondo; P. J. Gámez-montero; A. Babiano; R. Castilla

Description: LABSON, Dpt. of Fluid Mechanics, U.P.C., Spain. We study numerically the comparison between Lagrangian experiments on turbulent particle dispersion in 2-D turbulent flows performed, on the one hand, on the basis of direct numerical simulations (DNS) and, on the other hand, using kinematic simulations (KS). Eulerian space-time structure of both DNS and KS dynamics are not comparable, mostly due to the absence of strong coherent vortices and advection p...

Babiano, A., Basdevant, C., and Sadourny, R.: Structure functions and dispersion laws in two-dimensional turbulence, J. Atmos. Sci., 42, 942–949, 1985.; Babiano, A., Basdevant, C., Le Roy, P., and Sadourny, R.:. Single particle dispersion, Lagrangian structure function and Lagrangian energy spectrum in two-dimensional incompressible turbulence, J. Mar. Res., 45, 107–131, 1987.; Babiano,A., Basdevant, C., Le Roy, P., and Sadourny, R.: Relative dispersion in two-dimensiona...

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Multifractal Analysis of Vertical Profiles of Soil Penetration Res...

By: J. Paz-ferreiro; G. M. Siqueira; E. Vidal Vázquez; A. A. A. Montenegro; E. F. F. Silva

Description: Department of Rural Technology, Federal Rural University of Pernambuco, Dom Manoel de Medeiros s/n, 52171-900 Recife-PE, Brazil. Soil penetration resistance (PR) is widely used as an indirect indicator of soil strength. Soil PR is linked to basic soil properties and correlated to root growth and plant production, and as such it is extensively used as a practical tool for assessing soil compaction and to evaluate the effects of soil management. This study...

Armstrong, A. C.: On the fractal dimensions of some transient soil properties, J. Soil Sci., 37, 641–652, 1986.; ASAE: Soil cone penetrometer, ASAE standards, American Soc. Agric. Eng., S313, 2, St. Joseph, MI, 466 pp., 1986.; Biswas, A., Zeleke, T. B., and Si, B. C.: Multifractal detrended fluctuation analysis in examining scaling properties of the spatial patterns of soil water storage, Nonlin. Processes Geophys., 19, 227–238,

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Do Climate Simulations from Models Forced by Averaged Sea Surface ...

By: P. J. Roebber; A. A. Tsonis; J. B. Elsner

Description: Department of Goesciences, University of Wisconsin at Milwaukee, 3209 N. Maryland, Milwaukee, WI, USA 53211. Recently atmospheric general circulation models (AGCMs) forced by observed sea surface temperatures (SSTs) have offered the possibility of studying climate variability over periods ranging from years to decades. Such models represent and alternative to fully coupled asynchronous atmosphere ocean models whose long term integration remains problema...

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Intermittent Heating of the Solar Corona by Mhd Turbulence : Volum...

By: É. Buchlin

Description: Space and Atmospheric Physics group, Blackett Laboratory, Imperial College, London, UK. As the dissipation mechanisms considered for the heating of the solar corona would be sufficiently efficient only in the presence of small scales, turbulence is thought to be a key player in the coronal heating processes: it allows indeed to transfer energy from the large scales to these small scales. While Direct numerical simulations which have been performed ...

Abramenko, V I., Yurchyshyn, V B., Wang, H., Spirock, T J., and Goode, P R.: Scaling Behavior of Structure Functions of the Longitudinal Magnetic Field in Active Regions on the Sun, Astrophys. J., 577, 487–495, 2002.; Alexakis, A., Mininni, P D., and Pouquet, A.: Shell-to-shell energy transfer in magnetohydrodynamics. I. Steady state turbulence, Phys. Rev. E, 72, 046 301, 2005.; Bak, P., Tang, C., and Wiesenfeld, K.: Self-organized criticality – An explanation of $1/f$ n...

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On a Spectrum of Nonlinear Internal Waves in the Oceanic Coastal Z...

By: V. Novotryasov; A. Filonov

Description: Physics Department, University of Guadalajara, México. This paper studies the internal wave band of temperature fluctuation spectra in the coastal zone of Pacific ocean. It is observed that on the central Mexican Pacific Shelf in the high-frequency band of temperature spectra the spectral exponent tends to ~Ω-1 at the time of spring tide and Ω-2 at the time of neap tide. On the western shelf of the Japan/East Sea, in the Ω<<Ω<< N

Colosi, J. A. and the ATOS Group: A review of recent results on ocean acoustic wave propagation in random media: Basin scales, IEEE J. Oceanic Eng., 24, 138–155, 1999.; Filonov, A. E. and Konyaev, K. V.: Nonlinear Internal Waves near Mexico's Central Pacific Coast, edited by: Velasco Fuentes, O U., Sheinbaum, J., and Ochoa, J.: Nonlinear Processes in Geophysical Fluid Dynamics, Kluver Academic Publishers, 257–274, 2003.; Filonov, A. E. and Lavin, M. P.: Internal tides in...

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Permanent Bedforms in a Theoretical Model of Wave-sea-bed Interact...

By: D. Bercovici; J. M. Becker

Description: Department of Geology and Geophysics, University of Hawaii at Manoa, Honolulu, HI, 96822, USA. The interaction between sea waves and a deformable sea-bed is studied with a simple two-layer model in which the upper-layer fluid is inviscid and the lower-layer fluid is bi-viscous to account for non-Newtonian behaviour of sand and sediments. The nonlinear response of the system to periodic forcing by an external surface pressure is determined. It is shown t...

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Strongly Nonlinear, Simple Internal Waves in Continuously-stratifi...

By: K. R. Helfrich; L. A. Ostrovsky

Description: Zel Technologies and University of Colorado, Boulder, CO, USA. Strongly nonlinear internal waves in a layer with arbitrary stratification are considered in the hydrostatic approximation. It is shown that simple waves having a variable vertical structure can emerge from a wide class of initial conditions. The equations describing such waves have been obtained using the isopycnal coordinate as a variable. Emergence of simple waves from an initial Gaussian...

Apel, J. R., Ostrovsky, L. A., Stepanyants, Y. A., and Lynch, J. F.: Internal solitons in the ocean and their effect on underwater sound, J. Acoust. Soc. Amer., 121, 695–722, 2007.; Baines, P. G.: Topographic effects in stratified flows, Cambridge University Press, 482 pp., 1995.; Jiang, Q. and Smith R.: Ideal shocks in 2-layer flow. Part I: Under a rigid lid, Tellus, 53A, 129–145, 2001.; Chumakova, L., Menzaque, F. E., Milewski, P. A., Rosales, R. R., Tabak, E. G., and ...

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Lagrangian Study of Surface Transport in the Kuroshio Extension Ar...

By: M. V. Budyansky; S. V. Prants; M. Yu. Uleysky

Description: Laboratory of Nonlinear Dynamical Systems, Pacific Oceanological Institute of the Russian Academy of Sciences, 43 Baltiyskaya st., 690041 Vladivostok, Russia. Lagrangian approach is applied to study near-surface large-scale transport in the Kuroshio Extension area using a simulation with synthetic particles advected by AVISO altimetric velocity field. A material line technique is proposed and applied to find out the origin of water masses in cold-core cy...

Abraham, E. R. and Bowen, M. M.: Chaotic stirring by a mesoscale surface-ocean flow, Chaos, 12, 373–381, doi:10.1063/1.1481615, 2002.; Andrade-Canto, F., Sheinbaum, J., and Zavala Sansón, L.: A Lagrangian approach to the Loop Current eddy separation, Nonlin. Processes Geophys., 20, 85–96, doi:10.5194/npg-20-85-2013, 2013.; Buesseler, K. O., Jayne, S. R., Fisher, N. S., Ry...

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On the Possibility of Precursors of Earthquakes in Vlf Range Obser...

By: A. K. Gwal; D. K. Sondhiya; S. Kumar

Description: Space Science Laboratory, Department of Physics, Barkatullah University, Bhopal-462026, India. Very Low Frequency (VLF) disturbances in the ionospheric electric field observed by DEMETER satellite prior to three different earthquakes that occurred during the years 2008–2009 have been presented. The electromagnetic wave data has been analyzed for few days before the earthquake with special attention to the variation in spectral characteristics and non-li...

Antonov, N. V., Lanotte, A., and Mazzino, A.: Persistence of small-scale anisotropies and anomalous scaling in a model of magnetohydrodynamics turbulence, Phys. Rev. E, 61, 6586–6605, doi:10.1103/PhysRevE.61.6586, 2000.; Artemyev, A. V., Orlova, K. G., Mourenas, D., Agapitov, O. V., and Krasnoselskikh, V. V.: Electron pitch-angle diffusion: resonant scattering by waves vs. nonadiabatic effects, Ann. Geophys., 31, 148...

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A Novel Method for Analyzing the Process of Abrupt Climate Change ...

By: G. L. Feng; W. Hou; P. C. Yan

Description: College of Atmospheric Sciences, Lanzhou University, China. A climate system which is transitioning from one state to another is known as an abrupt climate change. Most of the recent studies regarding abrupt climate change have focused on the changes occurring before and after the abrupt change point, while little attention has been given to the transition process which occurs when the system breaks away from the original state to a new state. In...

Meehl, G. A., Branstator, G. W., and Washington, W. M.: Tropical Pacific interannual variability and CO2 climate change, J. Climate, 6, 42–63, 1993.; Alexander, R., Reinhard, C., and Andrey, G.: Multistability and critical thresholds of the Greenland ice sheet, Nat. Clim. Change, 2, 429–432, 2012.; Alley, R. B., Marotzke, J., Nordhaus, W. D., Overpeck, J. T., Peteet, D. M., Pielke, R. A., Pierrehumbert Jr., R. T., Rhines, P. B., Stocker, T. F., Talley, L. D., ...

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Theory and Observation of Double Discontinuities : Volume 11, Issu...

By: Y. C. Whang

Description: Catholic University of America, Room 107, Pangborn Hall, Washington, D. C. 20064, USA. Recent research using high-resolution magnetic field data to examine the interior structures of MHD shocks in interplanetary space and in the magnetotail led to a surprising discovery that a slow-mode shock is often followed by an adjoining rotational discontinuity layer on the postshock side. The thickness of each layer is of the order of a few ion inertial lengths. S...

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Scaling of Peak Flows with Constant Flow Velocity in Random Self-s...

By: B. M. Troutman; V. K. Gupta; R. Mantilla

Description: IIHR-Hydroscience & Engineering, The University of Iowa, Iowa City, IA, 52242, USA. A methodology is presented to understand the role of the statistical self-similar topology of real river networks on scaling, or power law, in peak flows for rainfall-runoff events. We created Monte Carlo generated sets of ensembles of 1000 random self-similar networks (RSNs) with geometrically distributed interior and exterior generators having parameters pi<...

Furey, P. and Gupta, V. K.: Effects of excess rainfall on the temporal variability of observed peak discharge power laws, Adv. Water Resour., 28, 1240–1253, 2005.; Furey, P. R. and Gupta, V. K.: Diagnosing peak-discharge power laws observed in rainfall-runoff events in Goodwin Creek experimental watershed, Adv. Water Resour., 30, 2387–2399, 2007.; Furey, P. R. and Troutman, B. M.: A consistent framework for Horton regression statistics that leads to a modified Hack'...

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Electron Acoustic Solitons in the Presence of an Electron Beam and...

By: G. S. Lakhina; S. V. Singh; R. Bharuthram; S. Devanandhan

Description: Indian Institute of Geomagnetism, New Panvel (West), Navi Mumbai, India. Arbitrary amplitude electron acoustic solitons are studied in an unmagnetized plasma having cold electrons and ions, superthermal hot electrons and an electron beam. Using the Sagdeev pseudo potential method, theoretical analysis is carried out by assuming superthermal hot electrons having kappa distribution. The results show that inclusion of an electron beam alters the minimum va...

Armstrong, T. P., Paonessa, M. T., Bell II, E. V., and Krimigis, S.M.: Voyager observations of Saturnian ion and electron phase space densities, J. Geophys. Res., 88, 8893–8904, 1983.; Berthomier, M., Pottelette, R., Malingre, M., and Khotyaintsev, Y.: Electron-acoustic solitons in an electron-beam plasma system, Phys. Plasmas, 7, 2987–2994, 2000.; Berthomier, M., Pottelette, R., Muschietti, L., Roth, I., and Carlson, C. W.: Scaling of 3D solitary waves observed by FAST ...

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Organisation of Joints and Faults from 1-cm to 100-km Scales Revea...

By: C. Castaing; D. Sornette; G. Ouillon

Description: Institut de Géodynamique, CNRS URA 1279, Rue A. Einstein, Sophia Antipolis, 06560 Vabonne, France. The classical method of statistical physics deduces the macroscopic behaviour of a system from the organization and interactions of its microscopical constituents. This kind of problem can often be solved using procedures deduced from the Renormalization Group Theory, but in some cases, the basic microscopic rail are unknown and one has to deal only with th...

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Reconnection Studies Under Different Types of Turbulence Driving :...

By: E. T. Vishniac; A. Lazarian; K. Otmianowska-mazur; G. Kowal

Description: Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão, 1226 – Cidade Universitária, CEP 05508-090, São Paulo/SP, Brazil. We study a model of fast magnetic reconnection in the presence of weak turbulence proposed by Lazarian and Vishniac (1999) using three-dimensional direct numerical simulations. The model has been already successfully tested in Kowal et al. (2009) confirming the dependencies of the reconnecti...

Alvelius, K.: Random forcing of three-dimensional homogeneous turbulence, \pof, 11, 1880–1889, 1999.; Ambrosiano, J., Matthaeus, W. H., Goldstein, M. L., and Plante, D.: Test particle acceleration in turbulent reconnecting magnetic fields, \jgr, 93, 14383–14400, 1988.; Armstrong, J. W., Rickett, B. J., and Spangler, S. R.: Electron density power spectrum in the local interstellar medium, \apj, 443, 209–221, 1995.; Balbus, S. A. and Hawley, J. F.: Instability, turbulence,...

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Analysis of the Geomagnetic Activity of the DSt Index and Self-aff...

By: M. Balikhin; S. A. Billings; H. L. Wei

Description: Department of Automatic Control and Systems Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK. The geomagnetic activity of the Dst index is analyzed using wavelet transforms and it is shown that the Dst index possesses properties associated with self-affine fractals. For example, the power spectral density obeys a power-law dependence on frequency, and therefore the Dst index c...

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