Thermospheric parameters’ long-term variations over the period including the 24/25 solar cycle minimum. Whether the CO2 increase effects are seen?

AbstractSunspot activity exhibits hemispheric asymmetry. We study the long-term variations in the hemispheric sunspot area from Kodaikanal white-light data during 1921 – 2011. The results on the presence or absence of double peak in an individual solar cycle, dominant hemispheric activity, and phase lag between the activities of northern and southern hemispheres, etc., are presented.

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Long-term variations in the north–south asymmetry of solar activity and solar cycle prediction, III: Prediction for the amplitude of solar cycle 25

New Astronomy ◽

10.1016/j.newast.2014.04.001 ◽

2015 ◽

Vol 34 ◽

pp. 54-64 ◽

Cited By ~ 27

Author(s):

J. Javaraiah

Keyword(s):

Solar Activity ◽

Solar Cycle ◽

The North ◽

South Asymmetry ◽

Long Term Variations

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Long Term Decrease of Stratospheric Ionization Near the 24-th Solar Cycle Minimum after G4 – Severe Geomagnetic Storm and GLE72 on September 8–10, 2017

10.7546/crabs.2018.08.10 ◽

2018 ◽

Author(s):

Peter I.Y. Velinov ◽

Yordan Tassev

Keyword(s):

Solar Cycle ◽

Geomagnetic Storm ◽

Cycle Minimum

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Long-term variations in meridional motion of sunspot groups: comparison of DPD and SOON data

Proceedings of the International Astronomical Union ◽

10.1017/s174392131800131x ◽

2018 ◽

Vol 13 (S340) ◽

pp. 51-52

Author(s):

J. Javaraiah

Keyword(s):

Solar Cycle ◽

Sunspot Group ◽

Group Data ◽

Solar Cycle 23 ◽

Meridional Motion ◽

The Mean ◽

Long Term Variations ◽

Sunspot Groups

AbstractWe have analyzed the Debrecen Photoheliographic Data (DPD) and the Solar Optical Observing Network (SOON) sunspot group data during the period 1977 – 2015 and find that during the maximum of solar cycle 23 there is a large difference in the mean meridional motion of sunspot groups determined from DPD and SOON data.

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4.7 Meteor Radar Rates and the Solar Cycle

International Astronomical Union Colloquium ◽

10.1017/s0252921100052064 ◽

1976 ◽

Vol 31 ◽

pp. 390-390

Author(s):

B.A. Lindblad

Keyword(s):

Solar Cycle ◽

Density Gradient ◽

Meteor Radar ◽

Atmospheric Density ◽

End Point ◽

Long Term Variations

Long-term variations in meteor radar rates, echo amplitudes, and meteor end-point heights have been observed. These variations appear to be controlled to a large extent by the solar cycle of activity. Exceptionally high echo rates in 1953, 1963 and 1972 coincide approximately with solar cycle minima. The long-term variations are explained in terms of a solar controlled change in the atmospheric density gradient at the meteor ablation level.

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Solar cycle and seasonal behaviour of quasi two and rive day oscillations in the time variations of fOF2

Annals of Geophysics ◽

10.4401/ag-4225 ◽

1994 ◽

Vol 37 (2) ◽

Author(s):

E. M. Apostolov ◽

L. Alberca ◽

D. Altadill

Keyword(s):

Solar Cycle ◽

Annual Variation ◽

Solar Cycles ◽

Density Maximum ◽

Plasma Drift ◽

Seasonal Behaviour ◽

Time Variations ◽

Periodogram Analysis ◽

Long Term Variations

Seasonal and solar cycle variations of the quasi-two- and five-day oscillation amplitudes off f0F2 are evaluated by moving periodogram analysis. The 23 year time series (1964-1986) of fOF2 hourly values of Kaliningrad (54.7°N, 20.62°E), covering the solar cycles 20 and 21, is used for the analysis. Long term variations of these amplitudes are modulated by the 11-year solar cycle and are simultaneously influenced by the geomagnetic activity. The annual variation of the quasi-two- and five-day oscillation amplitudes has very clear maxima near the equinoxes. The mechanism of the influence of the travelling planetary waves in the meteor wind region by vertical plasma drift to the F2-layer electron density maximum is discussed.

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