Observations of Hysteresis Between Flare Index and Some Solar Indices

Using flare index data sets for solar cycles 21 and 22 we find that flare index and some solar activity indicators show a hysteresis phenomenon. It is observed that total sunspot area, mean magnetic field and coronal index follow different paths for the ascending and descending phases of the solar cycles while saturation effect exists at the extreme phases. However, we notice that the separations between the paths are not the same during the past two cycles of 21 and 22.

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Possible traces of solar activity effect on the surface air temperature of mid-latitudes

Proceedings of the International Astronomical Union ◽

10.1017/s1743921309992894 ◽

2009 ◽

Vol 5 (S264) ◽

pp. 343-349

Author(s):

Ali Kilcik ◽

Atila Özgüç ◽

Jean-Pierre Rozelot

Keyword(s):

Solar Activity ◽

Air Temperature ◽

Surface Air Temperature ◽

Cyclic Behavior ◽

Data Sets ◽

Solar Cycles ◽

Index Data ◽

Activity Effect ◽

European Part Of Russia ◽

Flare Index

AbstractIn this study we investigate the effects of solar activity on the surface air temperature of mid-latitudes. This enables us to understand existence of solar activity effects on the temperature. We used surface air temperature and pressure data as climate parameters, and solar flare index data as solar activity indicator, for the 25 - 50 degree longitude and 30 - 70 degree latitude zone, including Turkey and European part of Russia. We considered the parameters temperature, pressure and flare index data for the period ranging from January 1975 to the end of December 2007, which covers almost three solar cycles, namely 21st, 22nd, and 23rd. We found some significant correlations between solar activity and surface air temperature for cycles 22 and 23 for some zones. We applied multitaper method to obtain the cyclic behavior of surface air temperature data sets. The most pronounced power peaks were found by this transform around 1.2 and 2.5 years which were reported earlier for some solar activity indicators. We concluded that signature of solar activity effect exists on surface air temperature of mid-latitudes where we studied.

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On the Prediction of Solar Cycles

Solar Physics ◽

10.1007/s11207-020-01760-7 ◽

2021 ◽

Vol 296 (1) ◽

Author(s):

V. Courtillot ◽

F. Lopes ◽

J. L. Le Mouël

Keyword(s):

Solar Activity ◽

Solar Cycle ◽

Transfer Function ◽

Singular Spectrum Analysis ◽

Activity Cycle ◽

Solar Activity Cycle ◽

Planetary Motion ◽

Data Sets ◽

Solar Cycles ◽

Jovian Planets

AbstractThis article deals with the prediction of the upcoming solar activity cycle, Solar Cycle 25. We propose that astronomical ephemeris, specifically taken from the catalogs of aphelia of the four Jovian planets, could be drivers of variations in solar activity, represented by the series of sunspot numbers (SSN) from 1749 to 2020. We use singular spectrum analysis (SSA) to associate components with similar periods in the ephemeris and SSN. We determine the transfer function between the two data sets. We improve the match in successive steps: first with Jupiter only, then with the four Jovian planets and finally including commensurable periods of pairs and pairs of pairs of the Jovian planets (following Mörth and Schlamminger in Planetary Motion, Sunspots and Climate, Solar-Terrestrial Influences on Weather and Climate, 193, 1979). The transfer function can be applied to the ephemeris to predict future cycles. We test this with success using the “hindcast prediction” of Solar Cycles 21 to 24, using only data preceding these cycles, and by analyzing separately two 130 and 140 year-long halves of the original series. We conclude with a prediction of Solar Cycle 25 that can be compared to a dozen predictions by other authors: the maximum would occur in 2026.2 (± 1 yr) and reach an amplitude of 97.6 (± 7.8), similar to that of Solar Cycle 24, therefore sketching a new “Modern minimum”, following the Dalton and Gleissberg minima.

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Solar-type periodicities in the climate variability of Northern Fennoscandia during the last three centuries: Real influence of solar activity or natural instability in the climate system

The Holocene ◽

10.1177/09596836211060487 ◽

2021 ◽

pp. 095968362110604

Author(s):

Maxim Ogurtsov ◽

Samuli Helama ◽

Risto Jalkanen ◽

Högne Jungner ◽

Markus Lindholm ◽

...

Keyword(s):

Solar Activity ◽

Climate Variability ◽

Western Siberia ◽

Climate System ◽

Solar Cycles ◽

Activity Data ◽

The Past ◽

Proxy Records ◽

Northern Fennoscandia ◽

Solar Type

Fifteen proxy records of summer temperature in Fennoscandia, Northern Europe and in Yamal and Taymir Peninsulas (Western Siberia) were analyzed for the AD 1700–2000 period. Century-long (70–100 year) and quasi bi-decadal periodicities were found from proxy records representing different parts of Fennoscandia. Decadal variation was revealed in a smaller number of records. Statistically significant correlations were revealed between the timescale-dependent components of temperature variability and solar cycles of Schwabe (~11 year), Hale (~22 year), and Gleissberg (сentury-long) as recorded in solar activity data. Combining the results from our correlation analysis with the evidence of solar-climatic linkages over the Northern Fennoscandia obtained over the past 20 years suggest that there are two possible explanations for the obtained solar-proxy relations: (a) the Sun’s activity actually influences the climate variability in Northern Fennoscandia and in some regions of the Northern Hemisphere albeit the mechanism of such solar-climatic linkages are yet to be detailed; (b) the revealed solar-type periodicities result from natural instability of climate system and, in such a case, the correlations may appear purely by chance. Multiple lines of evidence support the first assumption but we note that the second one cannot be yet rejected. Guidelines for further research to elucidate this question are proposed including the Fisher’s combined probability test in the presence of solar signal in multiple proxy records.

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The Downturn in Solar Activity during Solar Cycles 5 and 6

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000024425 ◽

1991 ◽

Vol 9 (2) ◽

pp. 330-331 ◽

Cited By ~ 6

Author(s):

J. O. Murphy

Keyword(s):

Solar Activity ◽

Radial Growth ◽

High Solar Activity ◽

Data Sets ◽

Solar Cycles ◽

Reservoir Model ◽

Proxy Data ◽

Annual Index ◽

Carbon Reservoir ◽

Lagged Correlation

AbstractThe atmospheric 14C record, the corresponding WM values derived from a carbon reservoir model, auroral numbers and the Zurich relative annual sunspot numbers all demonstrate a substantial downturn in solar activity for the duration of solar cycles 5 and 6. This reduction is also imbedded in some dendrochronological proxy data sets, which describe an annual index radial growth rate for trees at high-altitude sites. A significant lagged correlation can exist between tree-ring indices and the 11–year solar cycle during periods of high solar activity, a feature which is not evident during quiescent periods.

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Observation of Hysteresis between Solar Activity Indicators and p-mode Frequency Shifts for Solar Cycle 22

International Astronomical Union Colloquium ◽

10.1017/s0252921100064824 ◽

2000 ◽

Vol 179 ◽

pp. 357-360

Author(s):

S. C. Tripathy ◽

Brajesh Kumar ◽

Kiran Jain ◽

A. Bhatnagar

Keyword(s):

Solar Activity ◽

Solar Cycle ◽

Magnetic Activity ◽

Mode Frequency ◽

Hysteresis Phenomenon ◽

Data Sets ◽

Frequency Data ◽

Frequency Shifts ◽

Intermediate Degree

AbstractUsing intermediate degreep-mode frequency data sets for solar cycle 22, we find that the frequency shifts and magnetic activity indicators show a “hysteresis” phenomenon. It is observed that the magnetic indices follow different paths for the ascending and descending phases of the solar cycle while for radiative indices, the separation between the paths are well within the error limits.

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Periodic Variation of the North-South Asymmetry of Solar Activity Phenomena

International Astronomical Union Colloquium ◽

10.1017/s0252921100064447 ◽

2000 ◽

Vol 179 ◽

pp. 173-176

Author(s):

V. K. Verma

Keyword(s):

Solar Activity ◽

Periodic Variation ◽

The Sun ◽

Solar Cycles ◽

The North ◽

Sunspot Data ◽

Flare Index ◽

North And South ◽

South Asymmetry

AbstractWe report here a study of various solar activity phenomena occurring in both north and south hemispheres of the Sun during solar cycles 8–23. In the study we have used sunspot data for the period 1832–1976, flare index data for the period 1936–1993, Hα flare data 1993–1998 and solar active prominences data for the period 1957–1998. Earlier Verma reported long-term cyclic period in N-S asymmetry and also that the N-S asymmetry of solar activity phenomena during solar cycles 21, 22, 23 and 24 will be south dominated and the N-S asymmetry will shift to north hemisphere in solar cycle 25. The present study shows that the N-S asymmetry during solar cycles 22 and 23 are southern dominated as suggested by Verma.

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Solar cycles: the past evolution influence

Proceedings of the International Astronomical Union ◽

10.1017/s1743921309992572 ◽

2009 ◽

Vol 5 (S264) ◽

pp. 155-157

Author(s):

Alexis Klutsch ◽

Rubens Freire Ferrero

Keyword(s):

Solar Activity ◽

Solar Cycle ◽

Magnetic Activity ◽

Measured Data ◽

Physical Models ◽

Periodic Pattern ◽

Solar Cycles ◽

Future Evolution ◽

The Past ◽

Physical Phenomena

AbstractThe so-calledsolar cycleis generally characterized by the quasi-periodic oscillatory evolution of the photospheric spots number. This quasi-periodic pattern has always been an intriguing question. Several physical models were proposed to explain this evolution and many mathematical data analysis were employed to determine the principal frequencies noticeable in the measured data. Both approaches try to predict the future evolution of the solar activity and to understand the physical phenomena producing these cycles. Here we present the analysis of the sunspots number evolution using the time-delay approach. Our results show than the solar cycle can also be characterized by this behavior implying the influence of the past evolution over the present one, suggesting an histeresis mechanism, linked probably with magnetic activity.

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Dipolar and Quadrupolar Magnetic Field Evolution over Solar Cycles 21, 22, and 23

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311017492 ◽

2010 ◽

Vol 6 (S271) ◽

pp. 94-101 ◽

Cited By ~ 1

Author(s):

M. L. DeRosa ◽

A. S. Brun ◽

J. T. Hoeksema

Keyword(s):

Magnetic Field ◽

Spherical Harmonic ◽

Transport Model ◽

Activity Cycle ◽

Surface Flux ◽

Solar Activity Cycle ◽

Solar Photosphere ◽

Solar Cycles ◽

Flux Transport ◽

The Past

AbstractTime series of photospheric magnetic field maps from two observatories, along with data from an evolving surface-flux transport model, are decomposed into their constituent spherical harmonic modes. The evolution of these spherical harmonic spectra reflect the modulation of bipole emergence rates through the solar activity cycle, and the subsequent dispersal, shear, and advection of magnetic flux patterns across the solar photosphere. In this article, we discuss the evolution of the dipolar and quadrupolar modes throughout the past three solar cycles (Cycles 21–23), as well as their relation to the reversal of the polar dipole during each solar maximum, and by extension to aspects of the operation of the global solar dynamo.

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Solar Wind Parameters and Its Geoefficiency During Minimums of Four Solar Cycles

Известия Байкальского государственного университета ◽

10.17150/2500-2759.2021.31(4).508-514 ◽

2021 ◽

Vol 31 (4) ◽

pp. 508-514

Author(s):

Vitalii Degtyarev ◽

Georgy Popov ◽

Svetlana Chudnenko

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Solar Activity ◽

Geomagnetic Activity ◽

Statistical Processing ◽

Magnetic Activity ◽

Solar Cycles ◽

Deep Minimum ◽

Significant Difference ◽

Solar Wind Parameters

Recently a number of publications have appeared on the long and deep minimum in cycle 23 of solar activity. This interest is due to the fact that it turned out to be the longest and deepest in terms of the number of sunspots in the entire era of space exploration. The features of the minimum of cycle 23 of solar activity and the beginning of cycle 24 made it possible to assume that in the coming decades, a minimum of solar activity similar to the Dalton or Maunder minimum, leading to a global change in the earth's climate, may occur. Such assumptions make a detailed study of the influence of the minimum of solar cycle 23 on the parameters of the solar wind and the interplanetary magnetic field, as well as a comparison of this influence with similar manifestations in the three previous cycles very urgent. The work carried out statistical processing and analysis of data available in print and on the Internet on the indices of solar activity (W and F10.7), on geomagnetic activity, as well as on the parameters of the solar wind and interplanetary field. In contrast to other similar studies, when choosing time intervals for all cycles, only one — 12 months was used, which made it possible to exclude annual and semi-annual variations in solar wind parameters. For the considered minima of solar activity, the geoeffectiveness of the disturbed fluxes ICME, CIR, and Sheath was considered. A monotonic and very significant decrease in the geoeffectiveness of the ICME streams was found. Data processing on the hourly average values of the solar wind parameters at the minima of geomagnetic activity for 4 cycles confirmed the significant difference between cycle 23 and the previous ones in the behavior of the magnetic field. The cycle-by-cycle decrease in the geoeffectiveness of coronal ejections discussed in the press deserves a more detailed analysis using extensive data on magnetic activity indices.

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