Zobrazeno 1 - 10
of 116
pro vyhledávání: '"D. Altadill"'
Publikováno v:
Annales Geophysicae, Vol 22, Pp 1171-1176 (2004)
Solar cycle variations of the amplitudes of the 27-day solar rotation period reflected in the geomagnetic activity index Ap, solar radio flux F10.7cm and critical frequency foF2 for mid-latitude ionosonde station Moscow from the maximum of sunspot
Externí odkaz:
https://doaj.org/article/21fcf924d7cc4589be1989803c9baaa3
Publikováno v:
Annales Geophysicae, Vol 21, Pp 1577-1588 (2003)
Analyses of time-spatial variations of critical plasma frequency foF2 during the summer of 1998 reveal the existence of an oscillation activity with attributes of a 6-day westward propagating wave. This event manifests itself as a global scale
Externí odkaz:
https://doaj.org/article/68049840581542db82cec7633a934f21
Publikováno v:
Annales Geophysicae, Vol 20, Pp 1007-1021 (2002)
This study attempts to demonstrate changes in the ionospheric F1-region daytime ionization during geomagnetic storms. The F1-region is explored using available data from several European middle latitude and lower latitude observatories and a se
Externí odkaz:
https://doaj.org/article/a6737bbe92574d858167183fd082cdb7
Autor:
J. Laštovicka, D. Pancheva, D. Altadill, E. A. Benediktov, J. Boška, J. Bremer, M. Dick, K. Igarashi, P. Mlch, B. A. de la Morena, Z. T. Rapoport, V. A. Vyakhirev, B. O. Vugmeister, X. Zhang, B. Zolesi
Publikováno v:
Annales Geophysicae, Vol 17, Pp 1040-1052 (1999)
The CRISTA/MAHRSI experiment on board a space shuttle was accompanied by a broad campaign of rocket, balloon and ground-based measurements. Supporting lower ionospheric ground-based measurements were run in Europe and Eastern Asia between 1 Octobe
Externí odkaz:
https://doaj.org/article/776af374e1c9449da30eea1c02c79d6f
Publikováno v:
Annales Geophysicae, Vol 16, Pp 609-617 (1998)
The existence and development of the quasi-2-day oscillations in the plasma frequency variations of the F region at northern middle latitudes are investigated. A new approach to study the quasi-2-day oscillations is presented, using a methodology
Externí odkaz:
https://doaj.org/article/5868d9c6d2b045e98f8d51e5e3152893
Publikováno v:
Annales Geophysicae, Vol 16, Pp 168-175 (1998)
The relative contributions of quasi-periodic oscillations from 2 to 35 days to the variability of foF2 at middle northern latitudes between 42°N and 60°N are investigated. The foF2 hourly data for the whole solar cycle 21 (1976–1986) for four
Externí odkaz:
https://doaj.org/article/7e36edbd9e2f4b498d727969afa37b9d
Autor:
D. Altadill
Publikováno v:
Annales Geophysicae, Vol 14, Pp 716-724 (1996)
The presence and persistence of an 18-day quasi-periodic oscillation in the ionospheric electron density variations were studied. The data of lower ionosphere (radio-wave absorption at equivalent frequency near 1 MHz), middle and upper ionosphere
Externí odkaz:
https://doaj.org/article/67ff438806a7437c8b2597b748d34e14
Autor:
D. Altadill, C. Bianchi
Publikováno v:
Annals of Geophysics, Vol 48, Iss 6 (2005)
Studies of the dynamics of the ionosphere and its related phenomena are mainly based on Doppler Drift measurements. The time variation (ionisation/recombination) of plasma density, thermospheric wind and others can be observed by means of HF-radars.
Externí odkaz:
https://doaj.org/article/a9373b14dcda4ff790357f6d2183298e
Publikováno v:
Annals of Geophysics, Vol 47, Iss 2-3 Sup. (2004)
The aim of this work within the WP 3.1 of the COST 271 Action is the characterization of the variability introduced in the F-region ionosphere by -Planetary Wave Signatures- (PWS) and -Gravity Wave Signatures- (GWS). Typical patterns of percentage of
Externí odkaz:
https://doaj.org/article/3eef795675ad47359cc39bc7579242da
Autor:
J. Lastovicka, D. Altadill
Publikováno v:
Annals of Geophysics, Vol 39, Iss 4 (1996)
The statistical analysis of the 5-day and 10-day oscillations inferred in the upper and lower ionosphere in Central Europe from f0F2 measured in Pruhonice and the radio wave absorption in the lower ionosphere shows a remarkable degree of similarity f
Externí odkaz:
https://doaj.org/article/b8a4bc57bc594c72a197065a209d4df4