World Library  
  


 
  • Cover Image

Substorm Related Changes in Precipitation in the Dayside Auroral Z...

By: I. W. McCrea; E. Donovan; J. Manninen; E. E. Woodfield; P. C. Anderson; F. Honary; A. J. Kavanagh

Description: Department of Communication Systems, Lancaster University, Lancaster, UK. A period (08:10–14:40 MLT, 11 February 1997) of enhanced electron density in the D- and E-regions is investigated using EISCAT, IRIS and other complementary instruments. The precipitation is determined to be due to substorm processes occurring close to magnetic midnight. Energetic electrons drift eastward after substorm injection and precipitate in the morning sector. The pre...

Read More
  • Cover Image

On the Altitude Dependence of Transversely Heated O+ Distributions...

By: B. Klecker; H. Rème; M. Malingre; J.-a. Sauvaud; M. Bouhram; L. Kistler; W. Miyake; A. Blăgău

Description: Max-Planck-Institut für extraterrestrische Physik, Gießenbachstraße, D-85741 Garching, Germany. The present paper focuses on the altitude dependence of oxygen ion conics in the dayside cusp/cleft region. Here, combining oxygen data from the Akebono, Interball-2 and Cluster satellites allows, for the first time, one to follow the global development of energetic (up to ~10keV) ion outflow over a continuous and broad altitude range up to about 5.5 Earth ra...

Read More
  • Cover Image

Cluster Survey of the Mid-altitude Cusp – Part 2: Large-scale Morp...

By: B. Klecker; C. P. Escoubet; I. Dandouras; F. Pitout

Description: Laboratoire de Planétologie de Grenoble, CNRS/UJF, 122 rue de la Piscine, BP 53, 38041 Grenoble Cedex 9, France. In this second part of our statistical study of the mid-altitude cusp, we compare the cusp morphology, as seen in the Cluster ion spectrometer (CIS), to the interplanetary magnetic field (IMF) orientation. We first recall the method we have used a) to define the cusp properties, b) to sort IMF conditions or behaviour in classes, c) to determi...

Balogh, A., Carr, C. M., Acuña, M. H., Dunlop, M. W., Beek, T. J., Brown, P., Fornacon, K.-H., Georgescu, E., Glassmeier, K.-H., Harris, J., Musmann, G., Oddy, T., and Schwingenschuh, K.: The Cluster Magnetic Field Investigation: overview of in-flight performance and initial results, Ann. Geophys., 19, 1207–1217, 2001.; Bosqued, J.-M., Sauvaud, J. A., Rème, H., Crasnier, J., Galperin, Yu. I., Kovrazhkin, R. A., and Gladyshev, V. A.: Evidence for ion energy dispersion in ...

Read More
  • Cover Image

Ionospheric Currents Estimated Simultaneously from Champ Satellite...

By: A. Viljanen; O. Amm; H. Lühr; I. Sillanpää; A. Pulkkinen; P. Ritter

Description: GeoForschungsZentrum Potsdam, Telegrafenberg, D-14473 Potsdam, Germany. One important contribution to the magnetic field measured at satellite altitude and at ground level comes from the external currents. We used the total field data sampled by the Overhauser Magnetometer on CHAMP and the horizontal magnetic field measurements of the IMAGE ground-based magnetometer network to study the ionospheric Hall current system in the auroral regions. For the CH...

Read More
  • Cover Image

Microphysical Retrievals from Simultaneous Polarimetric and Profil...

By: P. B. Chilson; T. J. Schuur; M. P. Morris; A. Ryzhkov

Description: School of Meteorology/Atmospheric Radar Research Center, Norman, OK, USA. The character of precipitation detected at the surface is the final product of many microphysical interactions in the cloud above, the combined effects of which may be characterized by the observed drop size distribution (DSD). This necessitates accurate retrieval of the DSD from remote sensing data, especially radar as it offers large areal coverage, high spatial resolution, and ...

Balsley, B B. and Gage, K.: On the use of radars for operational profiling, B. Am. Meteorol. Soc., 63, 1009–1018, 1982.; Battan, L J.: Radar Observation of the Atmosphere, Univ. of Chicago Press, 1973.; Brandes, E., Zhang, G., and Vivekanandan, J.: Drop Size Distribution Retrieval with Polarimetric Radar, J. Appl. Meteor., 43, 461–475, 2004.; Brandes, E A., Zhang, G., and Vivekanandan, J.: Experiments in Rainfall Estimation with a Polarimetric Radar in a Subtropical Envi...

Read More
  • Cover Image

Effects of Convection Instability Due to Incompatibility Between O...

By: P. C. Chu; W. Cai

Description: CSIRO Division of Atmospheric Research, Aspendale, Victoria, Australia. The study demonstrates that an incompatibility between a surface temperature climatology and a given ocean model, into which the climatology is assimilated via Haney restoration, can cause model ocean climate drift and interdecadal oscillations when the ocean is switched to a weaker restoration. This is made using an idealized Atlantic Ocean model driven by thermal and wind forcing ...

Read More
  • Cover Image

Statistical Analysis of the Dependence of Large-scale Birkeland Cu...

By: C. L. Waters; B. J. Anderson; H. Korth

Description: The Johns Hopkins University, Applied Physics Laboratory, Laurel, MD, USA. The spatial distributions of large-scale field-aligned Birkeland currents have been derived using magnetic field data obtained from the Iridium constellation of satellites from February 1999 to December 2007. From this database, we selected intervals that had at least 45% overlap in the large-scale currents between successive hours. The consistency in the current distributions is...

Germany, G. A., Torr, D. G., Richards, P. G., Torr, M. R., and John, S.: Determination of Ionospheric Conductivities from FUV Auroral Emissions, J. Geophys. Res., 99, 23297–23305, 1989.; Green, D. L., Waters, C. L., Korth, H., and Anderson, B. J.: Validation of Southern Hemisphere Field-Aligned Currents Calculated from Iridium Magnetic Field Data, in: Australian Space Science Conference Series, edited by: Short, W. and Cairns, I., National Space Society of Australia Ltd,...

Read More
  • Cover Image

Subauroral Red Arcs as a Conjugate Phenomenon: Comparison of Ov1-1...

By: A. V. Pavlov

Description: Institute of Terrestrial Magnetism, Ionosphere and Radio-Wave Propagation, Russia Academy of Science. (IZMIRAN), Troitsk, Moscow Region, 142092, Russia. This study compares the OV1-10 satellite measurements of the integral airglow intensities at 630 nm in the SAR arc regions observed in the northern and southern hemisphere as a conjugate phenomenon, with the model results obtained using the time-dependent one-dimensional mathematical model of the Earth i...

Read More
  • Cover Image

Magnetopause Current as Seen by Cluster : Volume 23, Issue 3 (30/0...

By: A. Balogh; M. W. Dunlop

Description: SSTD, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, UK. The four-spacecraft, magnetic field measurements on Cluster can be combined to produce an accurate determination of the electric current in the magnetopause boundary during stable magnetopause crossings. For events that are planar on the scale of the spacecraft configuration, the thickness of the current layer can be accurately estimated from its magnetic profile at each spacecra...

Read More
  • Cover Image

The Emission of Oxygen Green Line and Density of O Atom Determined...

By: J. Xu; J.-b. Nee; H. Gao

Description: State Key Laboratory of Space Weather, CSSAR, Chinese Academy of Sciences, Beijing, China. Emissions of the 557.7 nm green line airglow observed by the ISUAL (Imager of Sprites and Upper Atmospheric Lightning) instrument on board the FORMOSAT-2 satellite in May and November 2008 are studied here to derive the density distributions of the atomic oxygen by using atmospheric parameters from MSISE-00 model and TIMED (Thermosphere Ionosphere Mesosphere Energe...

Barth, C. A. and Hildebrandt, A. F.: The 5577 A airglow emission mechanism, J. Geophys. Res., 66, 985–986, 1961.; Bates, D. R.: Excitation of 557.7 nm OI line in nightglow, Planet. Space Sci., 36, 883–889, 1988.; Capetanakis, F. P., Sondermann, F., Höser, S., and Stuhl, F.: Temperature dependence of the quenching of O(1S) by simple inorganic molecules, J. Chem. Phys., 98, 7883–7887, 1993.; Liu, G., Shepherd, G. G., and Roble, R. G.: Seasonal variations of the nighttime O...

Read More
  • Cover Image

Modelling of Mirror Mode Structures as Propagating Slow Magnetoson...

By: C. Z. Cheng; K. Stasiewicz

Description: National Cheng Kung University, Tainan, Taiwan. Cluster measurements in the magnetosheath with spacecraft separations of 2000 km indicate that magnetic pulsations interpreted as mirror mode structures are not frozen in plasma flow, but do propagate with speeds of up to ~50 km/s. Properties of these pulsations are shown to be consistent with propagating slow magnetosonic solitons. By using nonlinear two fluid theory we demonstrate that the well known cla...

Chew, G. F., Goldberger, M. L., and Low, E. F.: The Boltzmann equation and the one-fluid hydromagnetic equations in the absence of particle collisions, Proc. Roy. Soc. London, A236, 112–118, 1956.; Chust, T. and Belmont, G.: Closure of fluid equations in collisionless magnetoplasmas, Phys. Plasmas, 13, 012506, doi:10.1063/1.2138568, 2006.; Hasegawa, A.: Drift mirror instability in the magnetosphere, Phys. Fluids, 12, 2642, ...

Read More
  • Cover Image

Drift-alfvén Waves in Space Plasmas – Theory and Mode Identificati...

By: O. A. Pokhotelov; V. V. Krasnoselskikh; S. I. Shatalov; O. G. Onishchenko

Description: LPCE/CNRS, 3A, Avenue de la Recherche Scientifique, 45071 Orléans Cedex 2, France. The theory of drift-Alfvén waves with the spatial scales comparable to the ion Larmor radius is developed. The dispersion relation, the wave impedance and variations of the plasma density perturbations versus the wave frequency are investigated. The relevance of theoretical results obtained to the Cluster observations in the cusp and near a reconnection X line in the Eart...

Cheng, C. Z.: A kinetic-magnetohydrodynamic model for low-frequency phenomena, J. Geophys. Res., 96, 21156–21171, 1991.; Chmyrev, V. M., Bilichenko, S. V., Pokhotelov, O. A., Marchenko, V. A., Lazarev, V. I., Streltsov, A. V., and Stenflo, L.: Alfvén vortices and related phenomena in the magnetosphere, Physica Scripta, 38, 841–854, 1988.; Chaston, C. C., Phan, T. D., Bonnell, J. W., Mozer, F. C., Acuna, M., Goldstein, M. L., Balogh, A., Andre, M., Reme, H., and Fazakerle...

Read More
  • Cover Image

Wave Particle Interactions in the High-altitude Polar Cusp: a Clus...

By: H. Rème; B. Lavraud; T. Chust; B. Grison; A. Balogh; N. Cornilleau-wehrlin; F. Sahraoui; M. André

Description: Centre d’étude des Environnements Terrestre et Planétaires, 10/12 avenue de l’Europe, 78140, Vélizy, France. On 23 March 2002, the four Cluster spacecraft crossed in close configuration (~100 km separation) the high-altitude (10 RE) cusp region. During a large part of the crossing, the STAFF and EFW instruments have detected strong electromagnetic wave activity at low frequencies, especially when intense field-aligned proton fluxes were...

Read More
  • Cover Image

Profile of the Horizontal Wind Variance Near the Ground in Near Ne...

By: J. P. Frangi; S. Yahaya

Description: Equipe Géomatériaux & Environnement, Institut de Physique du Globe de Paris/Université Paris 7 – Denis Diderot, UMR 7154, case postale 89, 4 place Jussieu 75252 Paris cedex 05, France. This paper deals with the characteristics of the atmospheric turbulent flow in the vicinity of the ground, and particularly with the profile of the horizontal wind variance. The study is based on experimental measurements performed with fast cup anemometers located near th...

André, J. C., De Moor, G., Lacarrere, P., Therry, G., and Du Vachat, R.: Modelling the 24-hr Evolution of the Mean and Turbulent Structures of the Planetary Boundary Layer, J. Atmos. Sci., 35, 1861–1883, 1978.; Brook, R. R.: The influence of water vapor fluctuations on turbulent fluxes, Bound.-Lay. Meteorol., 15, 481–487, 1978.; Brutsaert, W.: The roughness length for water vapor, sensible heat, and others scalars, J. Atmos. Sci., 32, 2028–2031, 1975.; Busch, N. E.: On t...

Read More
  • Cover Image

The Greatest Soda-water Lake in the World and How it is Influenced...

By: Z. Şen; M. Kadioğlu; E. Batur

Description: Istanbul Technical University, Meteorology Department, Hydrometeorology Research Group, Maslak 80626 Istanbul, Turkey. Global warming resulting from increasing greenhouse gases in the atmosphere and the local climate changes that follow affect local hydrospheric and biospheric environments. These include lakes that serve surrounding populations as a fresh water resource or provide regional navigation. Although there may well be steady water-quality alter...

Read More
  • Cover Image

A Global Climatology for Equatorial Plasma Bubbles in the Topside ...

By: W. J. Burke; F. J. Rich; L. C. Gentile

Description: Institute for Scientific Research, Boston College, Chestnut Hill, MA, USA. We have developed a global climatology of equatorial plasma bubble (EPB) occurrence based on evening sector plasma density measurements from polar-orbiting Defense Meteorological Satellite Program (DMSP) spacecraft during 1989-2004. EPBs are irregular plasma density depletions in the post-sunset ionosphere that degrade communication and navigation signals. More than 14400 EPBs we...

Read More
  • Cover Image

Simulations of Resonant Alfvén Waves Generated by Artificial Hf He...

By: W. Lotko; A. V. Streltsov; D. Pokhotelov

Description: Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA. Numerical two-dimensional two-fluid MHD simulations of dynamic magnetosphere-ionosphere (MI) coupling have been performed to model the effects imposed on the auroral ionosphere by a powerful HF radio wave transmitter. The simulations demonstrate that modifications of the ionospheric plasma temperature and recombination due to artificial heating may trigger the ionospheric feedback ...

Read More
  • Cover Image

Nonlinear Sea Level Trends from European Tide Gauge Records : Volu...

By: M. E. Silva; S. M. Barbosa; M. J. Fernandes

Description: Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169–007 Porto, Portugal. Mean sea level is a variable of considerable interest in meteorological and oceanographic studies, particularly long-term sea level variation and its relation to climate changes. This study concerns the analysis of monthly mean sea level data from tide gauge stations in the Northeast Atlantic with long and continuous records. Much research effort on mean s...

Read More
  • Cover Image

Long Term Changes in Euv and X-ray Emissions from the Solar Corona...

By: C. J. Davis; M. Lockwood; E. M. Clarke; R. A. Bamford; S. A. Bell

Description: Rutherford Appleton Laboratory, Chilton, Oxfordshire, UK. Measurements of the ionospheric E region during total solar eclipses in the period 1932–1999 have been used to investigate the fraction of Extreme Ultra Violet and soft X-ray radiation, 8, that is emitted from the limb corona and chromosphere. The relative apparent sizes of the Moon and the Sun are different for each eclipse, and techniques are presented which correct the measurements and, theref...

Read More
  • Cover Image

Statistical Analysis of Solar Proton Events : Volume 22, Issue 6 (...

By: H. Mavromichalaki; A. Belov; M. Gerontidou; V. Kurt

Description: Institute of Nuclear Physics, Moscow State University, 119899 Vorobievy Gory, Moscow, Russia. A new catalogue of 253 solar proton events (SPEs) with energy >10MeV and peak intensity >10 protons/cm2.s.sr (pfu) at the Earth's orbit for three complete 11-year solar cycles (1970-2002) is given. A statistical analysis of this data set of SPEs and their associated flares that occurred during this time period is presented. It is outlined that 231 of...

Read More
 
1
|
2
|
3
Records: 1 - 20 of 45 - Pages: 



Copyright © World Library Foundation. All rights reserved. eBooks from World Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.