Annales Geophysicae Journal Impact Factor & Information

Publisher: European Geophysical Society, European Geosciences Union

Journal description

Prior to 2001 this journal was published by Springer. Annales Geophysicae (ANGEO) is an international, multi- and inter- disciplinary scientific journal for the publication of original articles and of short communications (Letters) for the sciences of the Sun-Earth system, including the science of Space Weather, the Solar-Terrestrial plasma physics, and the Earth's atmosphere and oceans.

Current impact factor: 1.71

Impact Factor Rankings

2015 Impact Factor Available summer 2016
2014 Impact Factor 1.709
2013 Impact Factor 1.676
2012 Impact Factor 1.518
2011 Impact Factor 1.842
2010 Impact Factor 1.62
2009 Impact Factor 1.648
2008 Impact Factor 1.66
2007 Impact Factor 1.427
2006 Impact Factor 1.293
2005 Impact Factor 1.45
2004 Impact Factor 1.61
2003 Impact Factor 1.031
2002 Impact Factor 1.189
2001 Impact Factor 1.199
2000 Impact Factor 1.76
1999 Impact Factor 1.727
1998 Impact Factor 1.423
1997 Impact Factor 1.245

Impact factor over time

Impact factor

Additional details

5-year impact 1.74
Cited half-life 8.30
Immediacy index 0.40
Eigenfactor 0.01
Article influence 0.80
Website Annales Geophysicae (1988) website
Other titles Annales geophysicae (Montrouge, France: 1988: Online), Annales geophysicae
ISSN 1432-0576
OCLC 41977993
Material type Document, Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

European Geosciences Union

  • Pre-print
    • Author can archive a pre-print version
  • Post-print
    • Author can archive a post-print version
  • Conditions
    • Authors retain copyright
    • Creative Commons Attribution License 3.0
    • Eligible UK authors may deposit in OpenDepot
    • Publisher's version/PDF may be used
    • All titles are open access journals
  • Classification

Publications in this journal

  • Y. Zhang · W. Wan · G. Li · L. Liu · L. Hu · B. Ning ·
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    ABSTRACT: We analyze the data recorded during December 2011–November 2012 by a digital ionosonde and a GPS (Global Positioning System) scintillation and (total electron content) TEC receiver collocated at Sanya (109.6° E, 18.3° N; dip lat. 12.8° N), a low-latitude station in the Chinese longitude sector, to carry out a comparative study of ionospheric scintillations and spread F. A good consistency between the temporal variations of GPS scintillation (represented by the S4 index) and of ionogram spread F (represented by the QF index) is found in the pre-midnight period during equinox. However in the post-midnight period during equinox and in the period from post-sunset to pre-sunrise during June solstice, moderate spread F is seen without concurrent GPS scintillation. The possible cause responsible for the difference between post-midnight GPS scintillation and spread F during equinox could be due to the decaying of 400 m scale irregularities associated with equatorial spread F. Regarding the irregularities producing moderate QF and low S4 indices during June solstice, we suggest that the frequently observed sporadic E (Es) layer and the medium-scale traveling ionospheric disturbances (MSTIDs) over Sanya could play important roles in triggering the June solstitial spread-F events.
    Annales Geophysicae 11/2015; 33(11):1421-1430. DOI:10.5194/angeo-33-1421-2015
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    ABSTRACT: A model of non-elliptic wavevector anisotropy is developed for the inertial-range spectrum of magnetohydrodynamic turbulence and is presented in the two-dimensional wavevector domain spanning the directions parallel and perpendicular to the mean magnetic field. The non-elliptic model is a variation of the elliptic model with different scalings along the parallel and the perpendicular components of the wavevectors to the mean magnetic field. The non-elliptic anisotropy model reproduces the smooth transition of the power-law spectra from an index of −2 in the parallel projection with respect to the mean magnetic field to an index of −5/3 in the perpendicular projection observed in solar wind turbulence, and is as competitive as the critical balance model to explain the measured frequency spectra in the solar wind. The parameters in the non-elliptic spectrum model are compared with the solar wind observations.
    Annales Geophysicae 11/2015; 33(11):1413-1419. DOI:10.5194/angeo-33-1413-2015
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    ABSTRACT: We analyzed pre-midnight equatorial F region observations made by the 30 MHz coherent backscatter radar of São Luis, Brazil between August 2010 and February 2012. These measurements were processed, and used to create monthly maps of the echo occurrence as a function of local time and height. The maps show the inter-annual variability associated with equatorial spread F (ESF) occurrence in the Brazilian longitude sector. We also constructed monthly curves of the evening vertical drifts, for the Brazilian sector, using measurements by the ion velocity meter (IVM) onboard the C/NOFS satellite. The IVM evening drifts show a good overall agreement with the Scherliess and Fejer (1999) empirical model. Measured and model drifts show the development of the pre-reversal enhancement (PRE) of the vertical plasma drifts during ESF season. Using joint radar and satellite measurements, we found that evening (18:00–18:30 LT) mean non-negative drifts provide a necessary but not sufficient condition for the occurrence of topside ESF echoes. Evening downward (negative) drifts preceded the absence of topside ESF irregularities.
    Annales Geophysicae 11/2015; 33(11):1403-1412. DOI:10.5194/angeo-33-1403-2015
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    ABSTRACT: A study of the quasi-5-day wave (5DW) was performed using meteor radars at conjugate latitudes in the Northern and Southern hemispheres. These radars are located at Esrange, Sweden (68° N) and Juliusruh, Germany (55° N) in the Northern Hemisphere, and at Tierra del Fuego, Argentina (54° S) and Rothera Station, Antarctica (68° S) in the Southern Hemisphere. The analysis was performed using data collected during simultaneous measurements by the four radars from June 2010 to December 2012 at altitudes from 84 to 96 km. The 5DW was found to exhibit significant short-term, seasonal, and interannual variability at all sites. Typical events had planetary wave periods that ranged between 4 and 7 days, durations of only a few cycles, and infrequent strongly peaked variances and covariances. Winds exhibited rotary structures that varied strongly among sites and between events, and maximum amplitudes up to ~ 20 m s−1. Mean horizontal velocity covariances tended to be largely negative at all sites throughout the interval studied.
    Annales Geophysicae 11/2015; 33(11):1349-1359. DOI:10.5194/angeo-33-1349-2015
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    ABSTRACT: The ionospheric slab thickness is defined as the ratio of the total electron content (TEC) to the ionospheric F2 layer peak electron density (NmF2). In this study, the slab thickness is determined by measuring the ionospheric TEC from dual-frequency Global Positioning System (GPS) data and the NmF2 from the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC). A statistical analysis of the diurnal, seasonal and spatial variation in the ionospheric slab thickness is presented along the longitude of 120° E in China and its adjacent region during the recent solar minimum phase (2007–2009). The diurnal ratio, defined as the maximum slab thickness to the minimum slab thickness, and the night-to-day ratio, defined as the slab thickness during daytime to the slab thickness during night-time, are both analysed. The results show that the TEC of the northern crest is greater in winter than in summer, whereas NmF2 is greater in summer than in winter. A pronounced peak of slab thickness occurs during the post-midnight (00:00–04:00 LT) period, when the peak electron density is at the lowest level. A large diurnal ratio exists at the equatorial ionization anomaly, and a large night-to-day ratio occurs near the equatorial latitudes and mid- to high latitudes. It is found that the behaviours of the slab thickness and the F2 peak altitude are well correlated at the latitudes of 30–50° N and during the period of 10:00–16:00 LT. This current study is useful for improvement of the regional model and accurate calculation of the signal delay of radio waves propagating through the ionosphere.
    Annales Geophysicae 10/2015; 33(10):1311-1319. DOI:10.5194/angeo-33-1311-2015
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    ABSTRACT: We analyze the results from numerical simulations of the magnetic field, the electric field and the plasma particle dynamics at the inner geospace under the effect of solar storms and magnetospheric substorms. An orbit-following model solves for the full-particle motion, employing a dynamic, solar wind-driven geomagnetic field with a description of the electric field due to plasma convection and magnetic induction, all cast in a form suitable for implementation in computer codes. The kinematic data from the test-particle simulations is statistically analyzed over the initial plasma state, and an estimation of the charged particle fluxes from different populations and of the ensemble-averaged Dst index (based on the ring and tail current contributions) is provided. The present model may serve as the final link in a Sun-to-Earth modeling chain of major solar eruptions, providing an estimation of the inner geospace response.
    Annales Geophysicae 10/2015;
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    ABSTRACT: The Cluster multi-point mission offers a unique collection of non-thermal continuum (NTC) radio waves observed in the 2–80 kHz frequency range over almost 15 years, from various view points over the radiating plasmasphere. Here we present rather infrequent case events, such as when primary electrostatic sources of such waves are embedded within the plasmapause boundary far from the magnetic equatorial plane. The spectral signature of the emitted electromagnetic waves is structured as a series of wide harmonic bands within the range covered by the step in plasma frequency encountered at the boundary. Developing the concept that the frequency distance df between harmonic bands measures the magnetic field magnitude B at the source (df = Fce, electron gyrofrequency), we analyse three selected events. The first one (studied in Grimald et al., 2008) presents electric field signatures observed by a Cluster constellation of small size (~ 200 to 1000 km spacecraft separation) placed in the vicinity of sources. The electric field frequency spectra display frequency peaks placed at frequencies fs = n df (n being an integer), with df of the order of Fce values encountered at the plasmapause by the spacecraft. The second event, taken from the Cluster tilt campaign, leads to a 3-D view of NTC waves ray path orientations and to a localization of a global source region at several Earth radii (RE) from Cluster (Décréau et al., 2013). The measured spectra present successive peaks placed at fs ~ (n+ 1/2) df. Next, considering if both situations might be two facets of the same phenomenon, we analyze a third event. The Cluster fleet, configured into a constellation of large size (~ 8000 to 25 000 km spacecraft separation), allows us to observe wide-banded NTC waves at different distances from their sources. Two new findings can be derived from our analysis. First, we point out that a large portion of the plasmasphere boundary layer, covering a large range of magnetic latitudes, is radiating radio waves. The radio waves are issued from multiple sources of small size, each related to a given fs series and radiating inside a beam of narrow cone angle, referred to as a beamlet. The beamlets illuminate different satellites simultaneously, at different characteristic fs values, according to the latitude at which the satellite is placed. Second, when an observing satellite moves away from its assumed source region (the plasmapause surface), it is illuminated by several beamlets, issued from nearby sources with characteristic fs values close to each other. The addition of radio waves blurs the spectra of the overall received electric field. It can move the signal peaks such that their position fs satisfiesfs = (n+α) df, with 0 < α < 1. These findings open new perspectives for the interpretation of NTC events displaying harmonic signatures.
    Annales Geophysicae 10/2015; 33(10):1285-1300. DOI:10.5194/angeo-33-1285-2015
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    ABSTRACT: Taking advantage of the Cluster satellite mission and especially the observations made by the instrument WHISPER to deduce the electron number density along the orbit of the satellites, we studied the relationships between the plasmapause positions (LPP) and the following LPP indicators: (a) solar wind coupling functions Bz (Z component of the interplanetary magnetic field vector, B, in GSM system), BV (related to the interplanetary electric field; B is the magnitude of the interplanetary magnetic field vector, V is solar wind velocity), and dΦmp/dt (which combines different physical processes responsible for the magnetospheric activity) and (b) geomagnetic indices Dst, Ap and AE. The analysis is performed separately for three magnetic local time (MLT) sectors (Sector1 – night sector (01:00–07:00 MLT); Sector2 – day sector (07:00–16:00 MLT); Sector3 – evening sector (16:00–01:00 MLT)) and for all MLTs taken together. All LPP indicators suggest the faster plasmapause response in the postmidnight sector. Delays in the plasmapause responses (hereafter time lags) are approximately 2–27 h, always increasing from Sector1 to Sector3. The obtained fits clearly resolve the MLT structures. The variability in the plasmapause is the largest for low values of LPP indicators, especially in Sector2. At low activity levels,LPP exhibits the largest values on the dayside (in Sector2) and the smallest on the postmidnight side (Sector1). Displacements towards larger values on the evening side (Sector3) and towards lower values on the dayside (Sector2) are identified for enhanced magnetic activity. Our results contribute to constraining the physical mechanisms involved in the plasmapause formation and to further study the still not well understood related issues.
    Annales Geophysicae 10/2015; 33(10):1271-1283. DOI:10.5194/angeo-33-1271-2015
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    ABSTRACT: The ion composition experiment on Cluster measures 3-D distributions in one spin of the spacecraft (4 s). These distributions often measure field-aligned ion beams (H+, He+ and O+) accelerated out of the ionosphere. The standard model of these beams relies on a quasi-static U-shaped potential model. The beams contain important information about the structure and distribution of the U-shaped potential structures. For example, a simple beam with a narrow velocity range tells us that the particles are accelerated going through a quasi-static U-shaped potential structure localized in space. A more complex beam with a large range of velocities varying smoothly (a few tens of kilometers per second to > 100 km s−1) tells us that the potential structure is extended and distributed along the magnetic field. The Cluster experiment has now revealed new features about the beams. Some beams are broken into many individual structures each with their own velocity. The U-shaped potential model would interpret the new features in terms of particles accelerated by narrow isolated potential structures maintained over an extended region of the magnetic field. Another interpretation is that these features arise as Cluster traverses toward the center of a small-scale U-shaped potential region detecting particles accelerated on different equipotential contours. The estimate of the distance of the adjacent contours is ~ 590–610 m at a Cluster height of ~ 3.5 RE. The observed dimensions map to ~ 295–305 m in the ionosphere, suggesting Cluster has measured the potential structure of an auroral arc.
    Annales Geophysicae 10/2015; 33(10):1263-1269. DOI:10.5194/angeo-33-1263-2015
  • N. Li ·
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    ABSTRACT: The air flow in a three-way balance between the Coriolis force, the centrifugal force and the pressure gradient force, i.e., the gradient wind, is discussed. The author studies formation mechanisms and possible existence of four types of gradient wind (the normal high, the normal low, the anomalous high and the anomalous low), and proposes reasonable explanation of the evolution of the gradient wind, especially for the anomalous high and the anomalous low, both of which are considered to be pure mathematical solutions and are overlooked in classic literature.
    Annales Geophysicae 10/2015; 33(10):1253-1261. DOI:10.5194/angeo-33-1253-2015
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    ABSTRACT: The aurorae at Jupiter are made up of many different features associated with a variety of generation mechanisms. The main auroral emission, also known as the main oval, is the most prominent of them as it accounts for approximately half of the total power emitted by the aurorae in the ultraviolet range. The energy of the precipitating electrons is a crucial parameter to characterize the processes at play which give rise to these auroral emissions, and the altitude of the emissions directly depends on this energy. Here we make use of far-UV (FUV) images acquired with the Advanced Camera for Surveys on board the Hubble Space Telescope and spectra acquired with the Space Telescope Imaging Spectrograph to measure the vertical profile of the main emissions. The altitude of the brightness peak as seen above the limb is ~ 400 km, which is significantly higher than the 250 km measured in the post-dusk sector by Galileo in the visible domain. However, a detailed analysis of the effect of hydrocarbon absorption, including both simulations and FUV spectral observations, indicates that FUV apparent vertical profiles should be considered with caution, as these observations are not incompatible with an emission peak located at 250 km. The analysis also calls for spectral observations to be carried out with an optimized geometry in order to remove observational ambiguities.
    Annales Geophysicae 10/2015; 33(10):1211-1219. DOI:10.5194/angeo-33-1211-2015
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    ABSTRACT: The main auroral emission at Jupiter generally appears as a quasi-closed curtain centered around the magnetic pole. This auroral feature, which accounts for approximately half of the total power emitted by the aurorae in the ultraviolet range, is related to corotation enforcement currents in the middle magnetosphere. Early models for these currents assumed axisymmetry, but significant local time variability is obvious on any image of the Jovian aurorae. Here we use far-UV images from the Hubble Space Telescope to further characterize these variations on a statistical basis. We show that the dusk side sector is ~ 3 times brighter than the dawn side in the southern hemisphere and ~ 1.1 brighter in the northern hemisphere, where the magnetic anomaly complicates the interpretation of the measurements. We suggest that such an asymmetry between the dawn and the dusk sectors could be the result of a partial ring current in the nightside magnetosphere.
    Annales Geophysicae 10/2015; 33(10):1203-1209. DOI:10.5194/angeo-33-1203-2015