Effects of the imf sector structure in the midlatitude troposphere and stratosphere

1986 ◽  
Vol 30 (4) ◽  
pp. 394-403 ◽  
Author(s):  
Jan Laštovička ◽  
F. Pechala
Keyword(s):  
Sector Structure ◽  
The Imf

The IMF sector structure effects in total ozone in central Europe

1989 ◽  
Vol 33 (2) ◽  
pp. 198-205 ◽  
Author(s):  
Jürgen Bremer ◽  
Jan Laštovička ◽  
L. Křivský
Keyword(s):  
Central Europe ◽  
Total Ozone ◽  
Sector Structure ◽  
The Imf

scholarly journals Comment on “Identification of the IMF sector structure in near-real time by ground magnetic data” by Janzhura and Troshichev (2011)

2021 ◽  
Vol 39 (2) ◽  
pp. 369-377
Author(s):  
Peter Stauning
Keyword(s):  
Solar Wind ◽  
Real Time ◽  
International Association ◽  
Magnetic Data ◽  
Reference Level ◽  
Sector Structure ◽  
Polar Cap ◽  
Ground Magnetic ◽  
The Imf

Abstract. The only published description of the solar wind sector (SS) term used for the reference level in the post-event and real-time derivation of the Polar Cap (PC) indices, PCN (Polar Cap North) and PCS (Polar Cap South), in the version endorsed by the International Association for Geomagnetism and Aeronomy (IAGA) is found in the commented publication, Janzhura and Troshichev: Identification of the IMF sector structure in near-real time by ground magnetic data, Annales Geophysicae, 29, 1491–1500, 2011. Actually, the publication has served as a basis for the index endorsement by IAGA in 2013. However, neither the illustrations nor the results presented there have been derived by the specified near real-time method. Figures 1, 6, 7, and 8 display values derived by post-event calculations based on daily medians smoothed over 7 d centred on the day of interest. Figures 2, 3, and 4 display observed values smoothed over 7 d, while the remaining Fig. 5 displays averages over 4 months. In summary, there are strong disagreements between indications in the title, abstract, and statements in the text compared to the actual results and their illustrations.

scholarly journals Interplanetary magnetic field and its possible effects on the mid-latitude ionosphere II

1994 ◽  
Vol 37 (2) ◽  
Author(s):  
Y. Tulunay
Keyword(s):  
Magnetic Field ◽  
Solar Cycle ◽  
Interplanetary Magnetic Field ◽  
Sector Structure ◽  
Quiet Time ◽  
Time Value ◽  
The Mean ◽  
The Imf

Using criticaI frequencies, f0F2 from the Uppsala, Lannion and Dourbes ionosonde stations, the possible effects of the orientation of the IMF on mid-latitude ionosphere are further investigated. For this purpose, the regular diurnal, seasonal and solar cycle variations in the f0F2 data were removed by subtracting the mean of f0F2 for the same UT on all the magnetically quiet days (Ap< 6) within 15 days around the IMF Bz turnings. This yields the deviation from the average quiet-time value ?f0F2. The data are sorted according to the polarity of the IMF Bz and the effects of the southward turnings are discussed. Hapgood et al. (1991), Tulunay et al. (1991), Tulunay and Rahman (1992) investigated the possible effects of the IMF on mid-latitude ionosphere by employing the Slough and Argentine Islands f0F2 data. In order to facilitate a comparison the same method of analysis is being adopted again. However, in the present work the southward polarity changes in IMF Bz with no consideration of the IMF sector structure were considered only.

scholarly journals Comments on quiet daily variation derivation in "Identification of the IMF sector structure in near-real time by ground magnetic data" by Janzhura and Troshichev (2011)

2013 ◽  
Vol 31 (7) ◽  
pp. 1221-1225 ◽  
Author(s):  
P. Stauning
Keyword(s):  
Solar Wind ◽  
Real Time ◽  
Daily Variation ◽  
Magnetic Data ◽  
Sector Structure ◽  
Polar Cap ◽  
Ground Magnetic ◽  
The Imf

Abstract. The description presented in the paper of the relations of the solar wind sector structure to the derivation of the quiet daily variation (QDC) in polar magnetic recordings used for calculation of polar cap (PC) indices is found to be unclear and not properly justified. The presented example on inclusion of a solar sector term in an actual QDC series is found to be questionable even on the authors' premises.

Regularities of the IMF Sector Structure in the Last 170 Years

2017 ◽  
Vol 13 (S335) ◽  
pp. 208-210
Author(s):  
Mikhail V. Vokhmyanin ◽  
Nadezhda V. Zolotova ◽  
Dmitry I. Ponyavin
Keyword(s):  
Magnetic Field ◽  
Large Scale ◽  
Heliospheric Current Sheet ◽  
Sector Structure ◽  
Saint Petersburg ◽  
The Past ◽  
Magnetospheric Currents ◽  
The 19Th Century ◽  
Made In ◽  
The Imf

AbstractThe interplanetary magnetic field (IMF) controls magnetospheric currents which cause variations of the ground-based magnetic field. Regular magnetic observations made in the 19th century allow us to infer daily IMF polarities back to 1844. The results coincide with satellite data in about 79% days. Moreover, for the most part of the 19th and 20th centuries, proxies obtained from various geomagnetic data (Helsinki, Saint-Petersburg, Potsdam, and Ekaterinburg) show the same patterns. This suggests that the reliability of the proxies is sufficient to study the IMF in the past. The large-scale organization of the IMF polarities, the so-called sector structure, reveals semi-centennial north-south displacements of the heliospheric current sheet (HCS).

scholarly journals Comment on Identification of the IMF sector structure in near-real time by ground magnetic data by Janzhura and Troshichev (2011)

2020 ◽  
Author(s):  
Peter Stauning
Keyword(s):  
Solar Wind ◽  
Real Time ◽  
International Association ◽  
Magnetic Data ◽  
Reference Level ◽  
Sector Structure ◽  
Polar Cap ◽  
Ground Magnetic ◽  
The Imf

Abstract. The only published description of the solar wind sector (SS) term used for the reference level in the post-event and real-time derivation of the Polar Cap (PC) indices, PCN (North) and PCS (South), in the version endorsed by the International Association for Geomagnetism and Aeronomy (IAGA) is found in the commented publication, Janzhura and Troshichev (2011): Identification of the IMF sector structure in near-real time by ground magnetic data, Annales Geophysicae, 29, 1491–1500. Actually, the publication has served as basis for the index endorsement by IAGA in 2013. However, neither the illustrations nor the results presented there have been derived by the specified near-real time method. Figs. 1, 6, 7, and 8 display values derived by post-event calculations based on daily medians smoothed over 7 days centred on the day of interest. Figs. 2, 3, and 4 display observed values smoothed over 7 days, while the remaining Fig. 5 displays averages over 4 months. In summary, there are strong disagreements between indications in the title, abstract, and statements in the text compared to the actual results and their illustrations.

scholarly journals Dependence of the IMF sector structure on the solar dipole tilt angle

2008 ◽  
Vol 113 (A7) ◽  
pp. n/a-n/a ◽  
Author(s):  
A. M. Du ◽  
W. Y. Xu ◽  
X. S. Feng
Keyword(s):  
Tilt Angle ◽  
Sector Structure ◽  
Dipole Tilt ◽  
The Imf

scholarly journals On the periodic variations of geomagnetic activity indices Ap and ap

1998 ◽  
Vol 16 (5) ◽  
pp. 510-517 ◽  
Author(s):  
H. Schreiber
Keyword(s):  
Solar Wind ◽  
Solar Cycle ◽  
Geomagnetic Activity ◽  
Sunspot Cycle ◽  
Solar Wind Plasma ◽  
Sector Structure ◽  
Interplanetary Physics ◽  
Before And After ◽  
Activity Indices ◽  
The Imf

Abstract. Yearly averages of geomagnetic activity indices Ap for the years 1967–1984 are compared to the respective averages of ν2·Bs, where v is the solar wind velocity and Bs is the southward interplanetary magnetic field (IMF) component. The correlation of both quantities is known to be rather good. Comparing the averages of Ap with ν2 and Bs separately we find that, during the declining phase of the solar cycle, ν2 and during the ascending phase Bs have more influence on Ap. According to this observation (using Fourier spectral analysis) the semiannual and 27 days, Ap variations for the years 1932–1993 were analysed separately for years before and after sunspot minima. Only those time-intervals before sunspot minima with a significant 27-day recurrent period of the IMF sector structure and those intervals after sunspot minima with a significant 28-28.5-day recurrent period of the sector structure were used. The averaged spectra of the two Ap data sets clearly show a period of 27 days before and a period of 28–29 days after sunspot minimum. Moreover, the phase of the average semiannual wave of Ap is significantly different for the two groups of data: the Ap variation maximizes near the equinoxes during the declining phase of the sunspot cycle and near the beginning of April and October during the ascending phase of the sunspot cycle, as predicted by the Russell-McPherron (R-M) mechanism. Analysing the daily variation of ap in an analogue manner, the same equinoctial and R-M mechanisms are seen, suggesting that during phases of the solar cycle, when ap depends more on the IMF-Bs component, the R-M mechanism is predominant, whereas during phases when ap increases as v increases the equinoctial mechanism is more likely to be effective.Key words. Interplanetary physics · Magnetic fields · Solar wind plasma · Solar wind · magnetosphere interaction

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