Variations of thermospheric winds in northern scandinavia between 1980 and 1986: A study of geomagnetic activity effects during the last solar cycle

1987 ◽  
Vol 9 (2) ◽  
pp. 197-214 ◽  
Author(s):  
David Rees ◽  
N. D. Lloyd ◽  
T. J. Fuller-Rowell ◽  
Ake Steen
Keyword(s):  
Solar Cycle ◽  
Geomagnetic Activity ◽  
Thermospheric Winds

scholarly journals Solar cycle effects in planetary geomagnetic activity: Analysis of 36-year long OMNI dataset

2000 ◽  
Vol 27 (17) ◽  
pp. 2797-2800 ◽  
Author(s):  
V. O. Papitashvili ◽  
N. E. Papitashvili ◽  
J. H. King
Keyword(s):  
Solar Cycle ◽  
Geomagnetic Activity ◽  
Activity Analysis

scholarly journals Extremely low geomagnetic activity during the recent deep solar cycle minimum

2011 ◽  
Vol 7 (S286) ◽  
pp. 200-209 ◽  
Author(s):  
E. Echer ◽  
B. T. Tsurutani ◽  
W. D. Gonzalez
Keyword(s):  
Solar Wind ◽  
Solar Cycle ◽  
Geomagnetic Activity ◽  
Solar Minimum ◽  
Solar Wind Speed ◽  
Sunspot Cycle ◽  
Cycle Minimum ◽  
Current Minimum ◽  
Solar Wind Parameters ◽  
Xix Century

AbstractThe recent solar minimum (2008-2009) was extreme in several aspects: the sunspot number, Rz, interplanetary magnetic field (IMF) magnitude Bo and solar wind speed Vsw were the lowest during the space era. Furthermore, the variance of the IMF southward Bz component was low. As a consequence of these exceedingly low solar wind parameters, there was a minimum in the energy transfer from solar wind to the magnetosphere, and the geomagnetic activity ap index reached extremely low levels. The minimum in geomagnetic activity was delayed in relation to sunspot cycle minimum. We compare the solar wind and geomagnetic activity observed in this recent minimum with previous solar cycle values during the space era (1964-2010). Moreover, the geomagnetic activity conditions during the current minimum are compared with long term variability during the period of available geomagnetic observations. The extremely low geomagnetic activity observed in this solar minimum was previously recorded only at the end of XIX century and at the beginning of the XX century, and this might be related to the Gleissberg (80-100 years) solar cycle.

scholarly journals The 22-year cycle in the geomagnetic 27-day recurrences reflecting on the F2-layer ionization

2004 ◽  
Vol 22 (4) ◽  
pp. 1171-1176 ◽  
Author(s):  
E. M. Apostolov ◽  
D. Altadill ◽  
M. Todorova
Keyword(s):  
Solar Cycle ◽  
Geomagnetic Activity ◽  
Activity Index ◽  
Solar Rotation ◽  
Rotation Period ◽  
Sunspot Cycle ◽  
Solar Cycles ◽  
Solar Radio Flux ◽  
Critical Frequency Fof2 ◽  
Northern And Southern Hemispheres

Abstract. 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 cycle 18 to the maximum of cycle 23 are examined. The analysis shows that there are distinct enhancements of the 27-day amplitudes for foF2 and Ap in the late declining phase of each solar cycle while the amplitudes for F10.7cm decrease gradually, and the foF2 and Ap amplitude peaks are much larger for even-numbered solar cycles than for the odd ones. Additionally, we found the same even-high and odd-low pattern of foF2 for other mid-latitude ionosonde stations in Northern and Southern Hemispheres. This property suggests that there exists a 22-year cycle in the F2-layer variability coupled with the 22-year cycle in the 27-day recurrence of geomagnetic activity. Key words. Ionosphere (mid-latitude ionosphere; ionosphere- magnetosphere interactions) – Magnetospheric physics (solar wind-magnetosphere interactions)

A Search for Periodic Variations in Geomagnetic Activity and Their Solar Cycle Dependence

1973 ◽  
Vol 7 (3) ◽  
pp. 135-140 ◽  
Author(s):  
H Hauska ◽  
S Abdel-Wahab ◽  
E Dyring
Keyword(s):  
Solar Cycle ◽  
Geomagnetic Activity ◽  
Cycle Dependence

A prediction of geomagnetic activity for solar cycle 23

1999 ◽  
Vol 104 (A4) ◽  
pp. 6871-6876 ◽  
Author(s):  
E. W. Cliver ◽  
A. G. Ling ◽  
J. E. Wise ◽  
L. J. Lanzerotti
Keyword(s):  
Solar Cycle ◽  
Geomagnetic Activity ◽  
Solar Cycle 23
Sign in / Sign up

Export Citation Format

Share Document