Annales Geophysicae

Công bố khoa học tiêu biểu

* Dữ liệu chỉ mang tính chất tham khảo

Sắp xếp:  
Combined CUTLASS, EISCAT and ESR observations of ionospheric plasma flows at the onset of an isolated substorm
Annales Geophysicae - Tập 18 - Trang 1073-1087 - 2000
T. K. Yeoman, J. A. Davies, N. M. Wade, G. Provan, S. E. Milan
On August 21st 1998, a sharp southward turning of the IMF, following on from a 20 h period of northward directed magnetic field, resulted in an isolated substorm over northern Scandinavia and Svalbard. A combination of high time resolution and large spatial scale measurements from an array of coherent scatter and incoherent scatter ionospheric radars, ground magnetometers and the Polar UVI imager ...... hiện toàn bộ
MUREX: a land-surface field experiment to study the annual cycle of the energy and water budgets
Annales Geophysicae - Tập 17 - Trang 838-854 - 1999
J.-C. Calvet, P. Bessemoulin, J. Noilhan, C. Berne, I. Braud, D. Courault, N. Fritz, E. Gonzalez-Sosa, J.-P. Goutorbe, R. Haverkamp, G. Jaubert, L. Kergoat, G. Lachaud, J.-P. Laurent, P. Mordelet, A. Olioso, P. Péris, J.-L. Roujean, J.-L. Thony, C. Tosca, M. Vauclin, D. Vignes
The MUREX (monitoring the usable soil reservoir experimentally) experiment was designed to provide continuous time series of field data over a long period, in order to improve and validate the Soil-vegetation-Atmosphere Transfer (SVAT) parameterisations employed in meteorological models. Intensive measurements were performed for more than three years over fallow farmland in southwestern France. To...... hiện toàn bộ
Negative ions in the auroral mesosphere during a PCA event around sunset
Annales Geophysicae - Tập 17 - Trang 782-793 - 1999
C. F. del Pozo, E. Turunen, T. Ulich
This is a study of the negative ion chemistry in the mesosphere above Tromsø using a number of EISCAT observations of high energy proton precipitation events during the last solar maximum, and in particular around sunset on 23 October, 1989. In these conditions it is possible to look at the relative importance of the various photodetachment and photodissociation processes controlling the concentra...... hiện toàn bộ
A possible mechanism for aurora formation
Annales Geophysicae - Tập 13 - Trang 698-703 - 1995
B. V. Rezhenov
A mechanism for the formation of aurora connected with the development of an interchange instability on the plasma sheet boundary layer (PSBL) is suggested. The PSBL is assumed to be deep inside the region of closed magnetic field lines. A system of equations connecting currents in the ionosphere and magnetosphere is solved numerically. It is found, using realistic ionospheric and magnetospheric ...... hiện toàn bộ
Upward high-energy field-aligned electron beams above the polar edge of auroral oval: observations from the SKA-3 instruments onboard the Auroral Probe (Interball-2)
Annales Geophysicae - Tập 16 - Trang 1046-1055 - 1998
V. A. Stepanov, Y. I. Galperin, A. K. Kuzmin, F. K. Shuiskaya, L. S. Gorn, B. A. Ilyin, M. V. Iovlev, A. A. Klimashov, I. I. Cherkashin, B. I. Khazanov, A. Y. Safronov
A new phenomenon was found at the polar edge of the auroral oval in the postmidnight-morning sectors: field-aligned (FA) high-energy upward electron beams in the energy range 20–40 keV at altitudes about 3 RE, accompanied by bidirectional electron FA beams of keV energy. The beam intensity often reaches more than 0.5 · 103 electrons/s · sr · keV · cm2, and the beams are observed for a relatively l...... hiện toàn bộ
Methods of detection and estimation errors in ST radar studies
Annales Geophysicae - Tập 12 - Trang 489-496 - 1994
S. Ferrat, M. Crochet
The classical theory of detection using the Neyman-Pearson principle is applied to stratosphere-troposphere (ST) radar signals. It is extended to provide information regarding the detection of weak signals which complements the detectability method usually employed in ST radar studies. It is shown that for ST radar signals of low amplitude and a detectability around 3 (a value commonly invoked in ...... hiện toàn bộ
Anisotropy of ionospheric irregularities determined from the amplitude of satellite signals at a single receiver
Annales Geophysicae - - 1999
E. D. Tereshchenko, B. Z. Khudukon, M. O. Kozlova, T. Nygrén
A new method of determining the anisotropy parameters of small-scale irregularities in the ionospheric F region is presented and experimental results are shown. The method is based on observations of amplitude fluctuations of radio waves transmitted by satellites flying above the F region. In practice, Russian navigational satellites are used and both the amplitude and the phase of the signal is m...... hiện toàn bộ
Cluster observations of reconnection due to the Kelvin-Helmholtz instability at the dawnside magnetospheric flank
Annales Geophysicae - Tập 24 Số 10 - Trang 2619-2643
K. Nykyri, A. Otto, B. Lavraud, C. Mouikis, L. M. Kistler, A. Balogh, H. Rème
Abstract. On 3 July 2001, the four Cluster satellites traversed along the dawnside magnetospheric flank and observed large variations in all plasma parameters. The estimated magnetopause boundary normals were oscillating in the z-direction and the normal component of the magnetic field showed systematic  2–3 min bipolar variations for 1 h when the IMF had a small positive bz-component and ...... hiện toàn bộ
Spatial distribution of upstream magnetospheric ≥50 keV ions
Annales Geophysicae - Tập 18 - Trang 42-46 - 1999
G. C. Anagnostopoulos, G. Argyropoulos, G. Kaliabetsos
We present for the first time a statistical study of ≥50 keV ion events of a magnetospheric origin upstream from Earth’s bow shock. The statistical analysis of the 50–220 keV ion events observed by the IMP-8 spacecraft shows: (1) a dawn-dusk asymmetry in ion distributions, with most events and lower intensities upstream from the quasi-parallel pre-dawn side (4 LT-6 LT) of the bow shock, (2) highes...... hiện toàn bộ
Pollutant transport in coastal areas with and without background wind
Annales Geophysicae - Tập 15 - Trang 476-486 - 1997
J. Camps, J. Massons, M. R. Soler, E. C. Nickerson
A three-dimensional meteorological model and a Lagrangian particle dispersion model are used to study the effects of a uniform large-scale wind on the dispersion of a non-reactive pollutant in a coastal region with complex terrain. Simulations are carried out both with and without a background wind. A comparison between model results and measured data (wind and pollutant concentrations) indicates ...... hiện toàn bộ
Tổng số: 695   
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 10