Solar cycle - Knowledge (XXG)

54:"The prediction for solar cycle 24 gave a smoothed sunspot number maximum of about 69 in the late Summer of 2013. The smoothed sunspot number reached 68.9 in August 2013 so the official maximum was at least that high. The smoothed sunspot number rose again towards this second peak over the last five months of 2016 and surpassed the level of the first peak (66.9 in February 2012). Many cycles are double peaked but this is the first in which the second peak in sunspot number was larger than the first. This was over five years into cycle 24. The predicted and observed size made this the smallest sunspot cycle since cycle 14 which had a maximum of 64.2 in February of 1906." 795: 929: 1576:

these flux transport processes also determine the "memory" of the solar cycle that plays an important role in physics-based predictions of the solar cycle. In particular, stochastically forced non-linear solar dynamo simulations establish that the solar cycle memory is short, lasting over one cycle, thus implying accurate predictions are possible only for the next solar cycle and not beyond. This postulate of a short one cycle memory in the solar dynamo mechanism was later observationally verified.

982:) in variance. A cycle of ~3.6 kyr, which is little known in literature, results in a mean variance of 0.6% only, does not seem to be Sun-related, although a gravitational origin cannot be ruled out. These 800-kyr-long EPICA suborbital records, which include millennial-scale Sun-related signals, fill an important gap in the field of solar cycles demonstrating for the first time the minor role of solar activity in the regional budget of Earth's climate system during the Mid-Late Pleistocene. 40: 403: 718: 620: 1195: 372: 51: 2184: 550:

strength of the solar polar field at the current minima correctly and forecasts a weak but not insignificant solar cycle 25 similar to or slightly stronger than cycle 24. Notably, they rule out the possibility of the Sun falling into a Maunder-minimum-like (inactive) state over the next decade. A preliminary consensus by a solar cycle 25 Prediction Panel was made in early 2019. The Panel, which was organized by NOAA's

7759: 675: 1612:. Additional models incorporating the influence of planetary forces on the Sun have since been proposed. However, the solar variability is known to be essentially stochastic and unpredictable beyond one solar cycle, which contradicts the idea of the deterministic planetary influence on solar dynamo. Modern dynamo models are able to reproduce the solar cycle without any planetary influence. 558:, based on the published solar cycle 25 predictions, concluded that solar cycle 25 will be very similar to solar cycle 24. They anticipate that the solar cycle minimum before cycle 25 will be long and deep, just as the minimum that preceded cycle 24. They expect solar maximum to occur between 2023 and 2026 with a sunspot range of 95 to 130, given in terms of the revised sunspot number. 7887: 997: 8229: 2192: 1572:

maximum strength. During the next cycle, differential rotation converts magnetic energy back from the poloidal to the toroidal field, with a polarity that is opposite to the previous cycle. The process carries on continuously, and in an idealized, simplified scenario, each 11-year sunspot cycle corresponds to a change in the polarity of the Sun's large-scale magnetic field.

8253: 8205: 690: 8241: 1510:, since the measured magnitude of recent solar variation is much smaller than the forcing due to greenhouse gases. Also, average solar activity in the 2010s was no higher than in the 1950s (see above), whereas average global temperatures had risen markedly over that period. Otherwise, the level of understanding of solar impacts on weather is low. 1704: 8217: 391:). The Sun was at a similarly high level of magnetic activity for only ~10% of the past 11,400 years. Almost all earlier high-activity periods were shorter than the present episode. Fossil records suggest that the solar cycle has been stable for at least the last 700 million years. For example, the cycle length during the 215: 1333:, cosmic ray variation may impact terrestrial low altitude cloud cover (unlike a lack of correlation with high altitude clouds), partially influenced by the solar-driven interplanetary magnetic field (as well as passage through the galactic arms over longer timeframes), but this hypothesis was not confirmed. 1465:

Early research attempted to correlate weather with limited success, followed by attempts to correlate solar activity with global temperature. The cycle also impacts regional climate. Measurements from the SORCE's Spectral Irradiance Monitor show that solar UV variability produces, for example, colder

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TSI is higher at solar maximum, even though sunspots are darker (cooler) than the average photosphere. This is caused by magnetized structures other than sunspots during solar maxima, such as faculae and active elements of the "bright" network, that are brighter (hotter) than the average photosphere.

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Faculae are bright magnetic features on the photosphere. They extend into the chromosphere, where they are referred to as plage. The evolution of plage areas is typically tracked from solar observations in the Ca II K line (393.37 nm). The amount of facula and plage area varies in phase with the

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was launched by the ACRIM group. The controversial 1989–1991 "ACRIM gap" between non-overlapping ACRIM satellites was interpolated by the ACRIM group into a composite showing +0.037%/decade rise. Another series based on the ACRIM data is produced by the PMOD group and shows a −0.008%/decade downward

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describes the observation that the maximum amplitudes of solar cycles are inversely proportional to the time between their solar minima and maxima. Therefore, cycles with larger maximum amplitudes tend to take less time to reach their maxima than cycles with smaller amplitudes. This effect was named

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The occurrence frequency of coronal mass ejections and flares is strongly modulated by the cycle. Flares of any given size are some 50 times more frequent at solar maximum than at minimum. Large coronal mass ejections occur on average a few times a day at solar maximum, down to one every few days at

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Time vs. solar latitude diagram of the radial component of the solar magnetic field, averaged over successive solar rotation. The "butterfly" signature of sunspots is clearly visible at low latitudes. Diagram constructed by the solar group at NASA Marshall Space Flight Center. The newest version can

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During the solar cycle's declining phase, energy shifts from the internal toroidal magnetic field to the external poloidal field, and sunspots diminish in number. At solar minimum, the toroidal field is, correspondingly, at minimum strength, sunspots are relatively rare and the poloidal field is at

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Activity cycles 21, 22 and 23 seen in sunspot number index, TSI, 10.7cm radio flux, and flare index. The vertical scales for each quantity have been adjusted to permit overplotting on the same vertical axis as TSI. Temporal variations of all quantities are tightly locked in phase, but the degree of

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wavelengths), which may or may not be accompanied by a coronal mass ejection, which consists of injection of energetic particles (primarily ionized hydrogen) into interplanetary space. Flares and CME are caused by sudden localized release of magnetic energy, which drives emission of ultraviolet and

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Solar cycle 25 began in December 2019. Several predictions have been made for solar cycle 25 based on different methods, ranging from very weak to strong magnitude. A physics-based prediction relying on the data-driven solar dynamo and solar surface flux transport models seems to have predicted the

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suggested that the alignment of the planets would alter the Sun's solar wind and, in turn, Earth's weather, culminating in multiple catastrophes on March 10, 1982. None of the catastrophes occurred. In 2023, a paper by Cionco et al. demonstrated the improbability that the suspected tidal effect on

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Solar dynamo models indicate that plasma flux transport processes in the solar interior such as differential rotation, meridional circulation and turbulent pumping play an important role in the recycling of the toroidal and poloidal components of the solar magnetic field. The relative strengths of

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ratios, cycles of 105, 131, 232, 385, 504, 805 and 2,241 years have been proposed, possibly matching cycles derived from other sources. Damon and Sonett proposed carbon 14-based medium- and short-term variations of periods 208 and 88 years; as well as suggesting a 2300-year radiocarbon period that

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Later papers showed that production of clouds via cosmic rays could not be explained by nucleation particles. Accelerator results failed to produce sufficient, and sufficiently large, particles to result in cloud formation; this includes observations after a major solar storm. Observations after

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entering the solar system from elsewhere in the galaxy. The frequency of solar eruptive events is modulated by the cycle, changing the degree of cosmic ray scattering in the outer solar system accordingly. As a consequence, the cosmic ray flux in the inner Solar System is anticorrelated with the

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eventually decay, releasing magnetic flux in the photosphere. This flux is dispersed and churned by turbulent convection and solar large-scale flows. These transport mechanisms lead to the accumulation of magnetized decay products at high solar latitudes, eventually reversing the polarity of the

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As each cycle begins, sunspots appear at mid-latitudes, and then move closer and closer to the equator until a solar minimum is reached. This pattern is best visualized in the form of the so-called butterfly diagram. Images of the Sun are divided into latitudinal strips, and the monthly-averaged

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revealed a direct relationship between the solar cycle and luminosity with a peak-to-peak amplitude of about 0.1%. Luminosity decreases by as much as 0.3% on a 10-day timescale when large groups of sunspots rotate across the Earth's view and increase by as much as 0.05% for up to 6 months due to

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Solar cycle 23 lasted 11.6 years, beginning in May 1996 and ending in January 2008. The maximum smoothed sunspot number (monthly number of sunspots averaged over a twelve-month period) observed during the solar cycle was 120.8 (March 2000), and the minimum was 1.7. A total of

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Until 2009, it was thought that 28 cycles had spanned the 309 years between 1699 and 2008, giving an average length of 11.04 years, but research then showed that the longest of these (1784–1799) may actually have been two cycles. If so then the average length would be only around

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Hale's observations revealed that the complete magnetic cycle—which would later be referred to as a Hale cycle—spans two solar cycles, or 22 years, before returning to its original state (including polarity). Because nearly all manifestations are insensitive to polarity, the 11-year solar cycle

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Emission from the Sun at centimetric (radio) wavelength is due primarily to coronal plasma trapped in the magnetic fields overlying active regions. The F10.7 index is a measure of the solar radio flux per unit frequency at a wavelength of 10.7 cm, near the peak of the observed solar radio

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that settle on the Earth's surface. Their concentration can be measured in tree trunks or ice cores, allowing a reconstruction of solar activity levels into the distant past. Such reconstructions indicate that the overall level of solar activity since the middle of the twentieth century stands

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records by using the benefits of the full-resolution methodology for time-series decomposition singular spectrum analysis, with a special focus on millennial-scale Sun-related signals. The quantitative impact of the three Sun-related cycles (unnamed ~9.7-kyr; proposed 'Heinrich-Bond' ~6.0-kyr;

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The solar cycle variation of 0.1% has small but detectable effects on the Earth's climate. Camp and Tung suggest that solar irradiance correlates with a variation of 0.18 K ±0.08 K (0.32 °F ±0.14 °F) in measured average global temperature between solar maximum and minimum.

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frequencies are also affected. High levels of sunspot activity lead to improved signal propagation on higher frequency bands, although they also increase the levels of solar noise and ionospheric disturbances. These effects are caused by impact of the increased level of solar radiation on the

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They collectively overcompensate for the irradiance deficit associated with the cooler, but less numerous sunspots. The primary driver of TSI changes on solar rotational and solar cycle timescales is the varying photospheric coverage of these radiatively active solar magnetic structures.

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10.7 years. Since observations began cycles as short as 9 years and as long as 14 years have been observed, and if the cycle of 1784–1799 is double then one of the two component cycles had to be less than 8 years in length. Significant amplitude variations also occur.

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solar minimum. The size of these events themselves does not depend sensitively on the phase of the solar cycle. A case in point are the three large X-class flares that occurred in December 2006, very near solar minimum; an X9.0 flare on Dec 5 stands as one of the brightest on record.

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forces emergence of the toroidal magnetic field through the photosphere, giving rise to pairs of sunspots, roughly aligned east–west with opposite magnetic polarities. The magnetic polarity of sunspot pairs alternates every solar cycle, a phenomenon described by

250:. In 1775, Horrebow noted how "it appears that after the course of a certain number of years, the appearance of the Sun repeats itself with respect to the number and size of the spots". The solar cycle however would not be clearly identified until 1843 when 1771:; see also the IPCC Fourth Assessment Report, in which the magnitude of variation in solar irradiance was revised downward, although the evidence of connections between solar variation and certain aspects of climate increased over the same time period: 2396:

Celia Martin-Puertas; Katja Matthes; Achim Brauer; Raimund Muscheler; Felicitas Hansen; Christof Petrick; Ala Aldahan; Göran Possnert; Bas van Geel (2 April 2012). "Regional atmospheric circulation shifts induced by a grand solar minimum".

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The magnetic field of the Sun flips during each solar cycle, with the flip occurring when the solar cycle is near its maximum. After two solar cycles, the Sun's magnetic field returns to its original state, completing what is known as a

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The solar magnetic field structures the corona, giving it its characteristic shape visible at times of solar eclipses. Complex coronal magnetic field structures evolve in response to fluid motions at the solar surface, and emergence of

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These variations have been successfully reproduced using models that employ magnetic flux continuity equations and observed sunspot numbers to quantify the emergence of magnetic flux from the top of the solar atmosphere and into the

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established that the solar cycle is a spatiotemporal magnetic process unfolding over the Sun as a whole. They observed that the solar surface is magnetized outside of sunspots, that this (weaker) magnetic field is to first order a

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Changes in ionization affect the aerosol abundance that serves as the condensation nucleus for cloud formation. During solar minima more cosmic rays reach Earth, potentially creating ultra-small aerosol particles as precursors to

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solar cycle, and they are more abundant than sunspots by approximately an order of magnitude. They exhibit a non linear relation to sunspots. Plage regions are also associated with strong magnetic fields in the solar surface.

1159:"). Variations about the average of up to −0.3% are caused by large sunspot groups and of +0.05% by large faculae and the bright network on a 7-10-day timescale Satellite-era TSI variations show small but detectable trends. 1245:

from after August 30, 1991, at the peak of cycle 22, to September 6, 2001, at the peak of cycle 23. Similar cycle-related variations are observed in the flux of solar UV or EUV radiation, as observed, for example, by the

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and collaborators, who in 1908 showed that sunspots were strongly magnetized (the first detection of magnetic fields beyond the Earth). In 1919 they identified a number of patterns that would collectively become known as

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have indicated that they also maintain large-scale magnetic fields and may display cycles of magnetic activity. The Sun has a radiative core surrounded by a convective envelope, and at the boundary of these two is the

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molecules by ultraviolet light. During a solar minimum, the decrease in ultraviolet light received from the Sun leads to a decrease in the concentration of ozone, allowing increased UVB to reach the Earth's surface.

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Chatzistergos T, Ermolli I, Krivova NA, Solanki SK, Banerjee D, Barata T, Belik M, et al. (July 2020). "Analysis of full-disc Ca II K spectroheliograms – III. Plage area composite series covering 1892–2019".

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The total solar irradiance (TSI) is the amount of solar radiative energy incident on the Earth's upper atmosphere. TSI variations were undetectable until satellite observations began in late 1978. A series of

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Even though it only accounts for a minuscule fraction of total solar radiation, the impact of solar UV, EUV and X-ray radiation on the Earth's upper atmosphere is profound. Solar UV flux is a major driver of

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X-ray radiation as well as energetic particles. These eruptive phenomena can have a significant impact on Earth's upper atmosphere and space environment, and are the primary drivers of what is now called

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level changed height in phase with solar activity during solar cycles 20–23. UV irradiance increase caused higher ozone production, leading to stratospheric heating and to poleward displacements in the

1283:(1 SFU = 10 W m Hz). It represents a measure of diffuse, nonradiative coronal plasma heating. It is an excellent indicator of overall solar activity levels and correlates well with solar UV emissions. 3345:

Owens, Mathew J.; Barnard, Luke A.; Pope, Benjamin J. S.; Lockwood, Mike; Usoskin, Ilya; Asvestari, Eleanna (19 August 2022). "Solar Energetic-Particle Ground-Level Enhancements and the Solar Cycle".

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Karoff, Christoffer; Jørgensen, Carsten Sønderskov; Senthamizh Pavai, V.; Arlt, Rainer (12 June 2019). "Christian Horrebow's Sunspot Observations – II. Construction of a Record of Sunspot Positions".

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remains the focus of research; however, the two halves of the Hale cycle are typically not identical: the 11-year cycles usually alternate between higher and lower sums of Wolf's sunspot numbers (the

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Both long-term and short-term variations in solar activity are proposed to potentially affect global climate, but it has proven challenging to show any link between solar variation and climate.

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would later describe how the magnitude at which the sunspots are "tilted"—with the leading spot(s) closer to the equator than the trailing spot(s)―grows with the latitude of these regions. (See

920:. Despite calculated radioisotope production rates being well correlated with the 400-year sunspot record, there is little evidence of the Suess cycle in the 400-year sunspot record by itself. 605:

Because the solar cycle reflects magnetic activity, various magnetically driven solar phenomena follow the solar cycle, including sunspots, faculae/plage, network, and coronal mass ejections.

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noticed a periodic variation in the average number of sunspots after 17 years of solar observations. Schwabe continued to observe the sunspot cycle for another 23 years, until 1867. In 1852,

6185:"Complexity of the Earth's space–atmosphere interaction region (SAIR) response to the solar flux at 10.7 cm as seen through the evaluation of five solar cycle two-line element (TLE) records" 5682:

Erlykin, A.; et al. (August 2013). "A review of the relevance of the 'CLOUD' results and other recent observations to the possible effect of cosmic rays on the terrestrial climate".

3968:; Milani, Franco; Bianchini, Antonio; Ortolani, Sergio (2016). "On the astronomical origin of the Hallstatt oscillation found in radiocarbon and climate records throughout the Holocene". 133:

by creating space weather and impacting space- and ground-based technologies as well as the Earth's atmosphere and also possibly climate fluctuations on scales of centuries and longer.

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trend. This 0.045%/decade difference can impact climate models. However, reconstructed total solar irradiance with models favor the PMOD series, thus reconciling the ACRIM-gap issue.

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Forster, P.; V. Ramaswamy; P. Artaxo; T. Berntsen; R. Betts; D.W. Fahey; J. Haywood; J. Lean; D.C. Lowe; G. Myhre; J. Nganga; R. Prinn; G. Raga; M. Schulz; R. Van Dorland (2007),

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Ultraviolet irradiance. The UV component varies by more than the total, so if UV were for some (as yet unknown) reason having a disproportionate effect, this might affect climate.

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fractional surface of sunspots is calculated. This is plotted vertically as a color-coded bar, and the process is repeated month after month to produce this time-series diagram.

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Wolf, R. (1852). "Neue untersuchungen über die periode der sonnenflecken und ihre bedeutung" [New investigations regarding the period of sunspots and its significance].

1592:. However, brown dwarfs lack radiative cores and tachoclines. Their structure consists of a solar-like convective envelope that exists from core to surface. Since they lack a 387:

isotope ratios. The level of solar activity beginning in the 1940s is exceptional – the last period of similar magnitude occurred around 9,000 years ago (during the warm

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designated the first numbered solar cycle to have started in February 1755 based on Schwabe's and other observations. Wolf also created a standard sunspot number index, the

6395:"Exploring the Physical Basis of Solar Cycle Predictions: Flux Transport Dynamics and Persistence of Memory in Advection- versus Diffusion-dominated Solar Convection Zones" 2508:

Brauer, Achim; Possnert, Göran; Aldahan, Ala; Błaszkiewicz, Mirosław; Słowinski, Michał; Ott, Florian; Dräger, Nadine; Mekhaldi, Florian; Adolphi, Florian (31 May 2018).

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Usoskin IG, Gallet Y, Lopes F, Kovaltsov GA, Hulot G (2016). "Solar activity during the Holocene: the Hallstatt cycle and its consequence for grand minima and maxima".

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Li, Pengbo; et al. (September 2018). "Sunspot cycles recorded in siliciclastic biolaminites at the dawn of the Neoproterozoic Sturtian glaciation in South China".

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K.L. Yeo; et al. (23 September 2014). "Reconstruction of total and spectral solar irradiance from 1974 to 2013 based on KPVT, SoHO/MDI and SDO/HMI observations".

2220:; Schüssler, Manfred; Mursula, Kalevi; Alanko, Katja (2003). "A Millennium Scale Sunspot Number Reconstruction: Evidence For an Unusually Active Sun Since the 1940s". 136:

Understanding and predicting the solar cycle remains one of the grand challenges in astrophysics with major ramifications for space science and the understanding of

1050:(SEU) events on electronics; at the same, the reduced flux of galactic cosmic radiation during solar maximum decreases the high-energy component of particle flux. 1866:

Vergleicht man nun die Zahl der Gruppen und der flecken-freien Tage mit einander, so findet man, dass die Sonnenflecken eine Periode von ungefähr 10 Jahren hatten

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The amount of ultraviolet UVB light at 300 nm reaching the Earth's surface varies by a few percent over the solar cycle due to variations in the protective

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SXT images, demonstrating the variation in solar activity during a solar cycle, from after August 30, 1991, to September 6, 2001. Credit: the Yohkoh mission of

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Echer, E; Kirchhoff, VWJH; Sahai, Y; Paes Leme, N (2001). "A study of the solar cycle signal on total ozone over low-latitude Brazilian observation stations".

1230:) emit more short-wavelength radiation. Since the upper atmosphere is not homogeneous and contains significant magnetic structure, the solar ultraviolet (UV), 961:

A 2021 study investigates the changes of the Pleistocene climate over the last 800 kyr from European Project for Ice Coring in Antarctica (EPICA) temperature (

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has long been thought to be the key to generating the Sun's large-scale magnetic field, recent research has questioned this assumption. Radio observations of

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of the radio wave in complex ways that can either facilitate or hinder communications. Forecasting of skywave modes is of considerable interest to commercial

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describes an amplitude modulation of solar cycles with a period of about 70–100 years, or seven or eight solar cycles. It was named after Wolfgang Gleißberg.

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This version of the sunspot butterfly diagram was constructed by the solar group at NASA Marshall Space Flight Center. The newest version can be found at [

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layer deep in the Sun may synchronize the solar dynamo. Their results were shown to be an artifact of the incorrectly applied smoothing method leading to

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Other effects include one study which found a relationship with wheat prices, and another one that found a weak correlation with the flow of water in the

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Solar irradiance varies systematically over the cycle, both in total irradiance and in its relative components (UV vs visible and other frequencies). The

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Some high-energy cosmic rays entering Earth's atmosphere collide hard enough with molecular atmospheric constituents that they occasionally cause nuclear

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amongst the highest of the past 10,000 years, and that epochs of suppressed activity, of varying durations have occurred repeatedly over that time span.

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An overview of three solar cycles shows the relationship between the solar cycle, galactic cosmic rays, and the state of Earth's near-space environment.

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but was not clearly identified until 1843. Solar activity, driven by both the solar cycle and transient aperiodic processes, governs the environment of

1869:" ('If one compares the number of groups and the sunspot-free days with one another, then one finds that the sunspots had a period of about 10 years') 359:

described the Sun's oscillatory magnetic field as having a quasi-steady periodicity of 22 years. It covered the oscillatory exchange of energy between

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The dipolar component of the solar magnetic field reverses polarity around the time of solar maximum and reaches peak strength at the solar minimum.

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yet still display solar-like magnetic activity, it has been suggested that solar magnetic activity is only generated in the convective envelope.

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The outward expansion of solar ejecta into interplanetary space provides overdensities of plasma that are efficient at scattering high-energy

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NOAA CD-ROM NGDC-05/01. This CD-ROM contains over 100 solar-terrestrial and related global data bases covering the period through April 1990.

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TSI varies in phase with the solar magnetic activity cycle with an amplitude of about 0.1% around an average value of about 1361.5 W/m (the "

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Cionco, Rodolfo G.; Kudryavtsev, Sergey M.; Soon, Willie W.-H. (May 2023). "Tidal Forcing on the Sun and the 11-Year Solar-Activity Cycle".

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Wu, C.J.; Krivova, N.; Solanki, S.K.; Usoskin, I.G. (2018). "Solar total and spectral irradiance reconstruction over the last 9000 years".

6352:"A Proposed Paradigm for Solar Activity Dynamics Mediated via Turbulent Pumping of Magnetic Flux in Babcock-Leighton-type Solar Dynamics" 2437:; Mursula, K.; Arlt, R.; Kovaltsov, G. A. (2009). "A solar cycle lost in 1793–1800: Early sunspot observations resolve the old mystery". 7289: 1637: 7222: 3115:

Chatzistergos, Theodosios; Ermolli, Ilaria; Krivova, Natalie A.; Barata, Teresa; Carvalho, Sara; Malherbe, Jean-Marie (November 2022).

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In the opposite hemisphere (that is, on the other side of the solar equator) these regions tend to have the opposite leading polarity.

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While magnetic field changes are concentrated at sunspots, the entire sun undergoes analogous changes, albeit of smaller magnitude.

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overall level of solar activity. This anticorrelation is clearly detected in cosmic ray flux measurements at the Earth's surface.

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activity, which bridge the time gap between the end of the usable cosmogenic isotope data and the start of modern satellite data.

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Chatzistergos, Theodosios; Ermolli, Ilaria; Solanki, Sami K.; Krivova, Natalie A.; Giorgi, Fabrizio; Yeo, Kok Leng (June 2019).

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solar magnetic fields which is mediated by solar plasma flows which also provides energy to the dynamo system at every step. At

1323:. Clouds formed from greater amounts of condensation nuclei are brighter, longer lived and likely to produce less precipitation. 576:. The first peak reached 99 in 2011 and the second in early 2014 at 101. Cycle 24 ended in December 2019 after 11.0 years. 7187: 551: 7154: 2714: 1978:

March 2010, Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany. ISSN 1614-4961 (accessed 19 July 2015)

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magnetism appears to be the primary cause (96%) of 1996–2013 TSI variation. The ratio of ultraviolet to visible light varies.

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action in the solar interior. For reasons not yet understood in detail, sometimes these structures lose stability, leading to

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Labitzke K.; Matthes K. (2003). "Eleven-year solar cycle variations in the atmosphere: observations, mechanisms and models".

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Proceedings of the 1st Solar and Space Weather Euroconference, 25–29 September 2000, Santa Cruz de Tenerife, Tenerife, Spain

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Tapping K.F. (1987). "Recent solar radio astronomy at centimeter wavelength: the temporal variability of the 10.7-cm flux".

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Periodicity of solar activity with periods longer than the solar cycle of about 11 (22) years has been proposed, including:

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or 'HF' radio spectrum that are most affected by these solar and ionospheric variances. Changes in solar output affect the

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since the 1970s. TSI measurements varied from 1355 to 1375 W/m across more than ten satellites. One of the satellites, the

7739: 6014:" page 5. Journal of Atmospheric and Solar-Ter restrial Physics on Space Climate, March 2010. Accessed: 20 September 2014. 4493:"A Bayesian Model for Inferring Total Solar Irradiance From Proxies and Direct Observations: Application to the ACRIM Gap" 635:

The Sun's apparent surface, the photosphere, radiates more actively when there are more sunspots. Satellite monitoring of

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Solar cycle 24 began on 4 January 2008, with minimal activity until early 2010. The cycle featured a "double-peaked"

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S. Poluianov; I. Usoskin (2014). "Critical Analysis of a Hypothesis of the Planetary Tidal Influence on Solar Activity".

5756:"Cross-spectrally coherent ~10.5- and 21-year biological and physical cycles, magnetic storms and myocardial infarctions" 2841: 7744: 7182: 5755: 2959:

Willson RC, Gulkis S, Janssen M, Hudson HS, Chapman GA (February 1981). "Observations of Solar Irradiance Variability".

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Willson R.C.; Gulkis S.; Janssen M.; Hudson H.S.; Chapman G.A. (1981). "Observations of solar irradiance variability".

4079:"Solar Variability: climatic change resulting from changes in the amount of solar energy reaching the upper atmosphere" 4059:

Damon, Paul E., and Sonett, Charles P., "Solar and terrestrial components of the atmospheric C-14 variation spectrum,"

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Along with the approximately 11-year sunspot cycle, a number of additional patterns and cycles have been hypothesized.

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Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007

4166:"Quantitative impact of astronomical and sun-related cycles on the Pleistocene climate system from Antarctica records" 6446:"Turbulent Pumping of Magnetic Flux Reduxes Solar Cycle Memory and thus Impacts Predictability of the Sun's Activity" 6154: 5754:

Halberg, F; Cornélissen, G; Otsuka, K; Watanabe, Y; Katinas, GS; Burioka, N; Delyukov, A; Gorgo, Y; Zhao, Z (2000).

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Braun, H; Christl, M; Rahmstorf, S; Ganopolski, A; Mangini, A; Kubatzki, C; Roth, K; Kromer, B (10 November 2005).

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The increased irradiance during solar maximum expands the envelope of the Earth's atmosphere, causing low-orbiting

912:, is a cycle present in radiocarbon proxies of solar activity with a period of about 210 years. It was named after 151:, since the measured magnitude of recent solar variation is much smaller than the forcing due to greenhouse gases. 125:

This cycle has been observed for centuries by changes in the Sun's appearance and by terrestrial phenomena such as

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Chatzistergos T, Krivova NA, Ermolli I, Kok Leng Y, Mandal S, Solanki SK, Kopp G, Malherbe JM (1 December 2021).

3288:

Owens, Mathew J.; Lockwood, Mike; Barnard, Luke A.; Scott, Chris J.; Haines, Carl; Macneil, Allan (20 May 2021).

2748: 1405: 1320: 1058: 779: 2286:

Luthardt, Ludwig; Rößler, Ronny (February 2017). "Fossil forest reveals sunspot activity in the early Permian".

1069:) therefore incorporate a radiation-shielded "storm shelter" for astronauts to retreat to during such an event. 223:(1816–1893), Swiss astronomer, carried out historical reconstruction of solar activity back to the 17th century. 5536: 5511: 3873:"The ~ 2400-year cycle in atmospheric radiocarbon concentration: bispectrum of C data over the last 8000 years" 2620:"Prediction of the strength and timing of sunspot cycle 25 reveal decadal-scale space environmental conditions" 2570: 1447: 7233: 5277:"The influence of solar-modulated regional circulations and galactic cosmic rays on global cloud distribution" 5225: 1466:

winters in the U.S. and northern Europe and warmer winters in Canada and southern Europe during solar minima.

301: 7415: 6155:"Changes in Atmospheric Constituents and Radiative Forcing: § 2.9.1 Uncertainties in Radiative Forcing" 5459: 4022: 3624: 2222: 1793: 1432: 1267: 794: 251: 3742:"Reconstruction and Prediction of Variations in the Open Solar Magnetic Flux and Interplanetary Conditions" 828: 7714: 7557: 7450: 7028:

Dziembowski, W.A.; P.R. Goode; J. Schou (2001). "Does the sun shrink with increasing magnetic activity?".

5914:

Ineson S.; Scaife A.A.; Knight J.R.; Manners J.C.; Dunstone N.J.; Gray L.J.; Haigh J.D. (9 October 2011).

5476: 5181: 1551:, the external poloidal dipolar magnetic field is near its dynamo-cycle minimum strength, but an internal 1412:. During the "peaks" of the solar cycle, the ionosphere becomes increasingly ionized by solar photons and 1148:

is an estimated 0.07 percent brighter during the mid-cycle solar maximum than the terminal solar minimum.

928: 31: 2778: 1772: 8273: 7781: 7610: 7430: 7262: 3728: 2510:"Synchronizing 10Be in two varved lake sediment records to IntCal13 14C during three grand solar minima" 1552: 1544: 1507: 1096: 1066: 1031: 758: 739: 652: 360: 355:, and that this dipole undergoes polarity reversals with the same period as the sunspot cycle. Horace's 289: 278: 148: 6157:, in Solomon, S.; D. Qin; M. Manning; Z. Chen; M. Marquis; K.B. Averyt; M. Tignor; H.L. Miller (eds.), 406:

Solar activity events recorded in radiocarbon. Present period is on right. Values since 1900 not shown.

7169: 6224:

Hale, G. E.; Ellerman, F.; Nicholson, S. B.; Joy, A. H. (1919). "The Magnetic Polarity of Sun-Spots".

2859: 8177: 8172: 7694: 7664: 7482: 7299: 7130: 7129:. The Solar Cycle and Terrestrial Climate. Vol. 463. ESA Publications Division. pp. 51–60. 7047: 7008: 6971: 6934: 6877: 6817: 6713: 6660: 6613: 6561: 6467: 6416: 6296: 6233: 6196: 6086: 6037: 6026:"[Impact of variations in solar activity on hydrological decadal patterns in northern Italy]" 5977: 5932: 5843: 5701: 5654: 5605: 5564: 5523: 5468: 5451: 5419: 5366: 5288: 5173: 5112: 5061: 5024: 4983: 4924: 4875: 4803: 4766: 4719: 4658: 4608: 4555: 4504: 4463: 4412: 4371: 4306: 4251: 4177: 4120: 3987: 3931: 3884: 3807: 3753: 3703: 3633: 3573: 3520: 3461: 3364: 3301: 3254: 3203: 3138: 3081: 3025: 2968: 2925: 2695: 2641: 2521: 2456: 2408: 2343: 2297: 2241: 2143: 2087: 2029: 1912: 1812: 1647: 1642: 1287: 1174: 208:(1789–1875), German astronomer, discovered the solar cycle through extended observations of sunspots. 130: 6158: 5643:"Cosmic rays, aerosol formation and cloud-condensation nuclei: sensitivities to model uncertainties" 5186: 4962:"Reconstructing solar irradiance from historical Ca II K observations. I. Method and its validation" 1014:

polar fields (notice how the blue and yellow fields reverse in the Hathaway/NASA/MSFC graph above).

8257: 7514: 5481: 4492: 4108: 1231: 1219: 297: 274: 137: 7089:

Grand Phases On The Sun: The case for a mechanism responsible for extended solar minima and maxima

1751:"6.11 Total Solar Irradiance—Figure 6.6: Global, annual mean radiative forcings (1750 to present)" 717: 180:

refer to periods of maximum and minimum sunspot counts. Cycles span from one minimum to the next.

8245: 8233: 7600: 7332: 7063: 7037: 6987: 6950: 6924: 6867: 6833: 6807: 6729: 6703: 6676: 6650: 6579: 6551: 6508: 6457: 6406: 6363: 6104: 6055: 5993: 5717: 5691: 5623: 5382: 5356: 5085: 4973: 4942: 4893: 4735: 4692: 4624: 4598: 4528: 4453: 4442:"ACRIM-gap and total solar irradiance revisited: Is there a secular trend between 1986 and 1996?" 4361: 4330: 4269: 4241: 4086: 4003: 3977: 3947: 3921: 3825: 3797: 3719: 3693: 3649: 3597: 3536: 3479: 3388: 3354: 3327: 3227: 3193: 3162: 3128: 3097: 3071: 3015: 2941: 2631: 2472: 2446: 2359: 2313: 2265: 2231: 2167: 2103: 2077: 2019: 1944: 1928: 1850: 1828: 1802: 1617: 1371: 1339: 1047: 336: 308: 231: 6999:

Foukal, Peter; et al. (1977). "The effects of sunspots and faculae on the solar constant".

6694:

F. Stefani; A. Giesecke; T. Weier (May 2019). "A Model of a Tidally Synchronized Solar Dynamo".

6308: 1622:

the Sun driven by Venus and Jupiter were significant on whole solar tidal generating potential.

1559:, is near its maximum strength. At this point in the dynamo cycle, buoyant upwelling within the 402: 293: 6598: 3559:"Possible solar origin of the 1,470-year glacial climate cycle demonstrated in a coupled model" 2898: 7734: 7649: 7455: 7138: 7093: 6903: 6780: 6497:"Solar Cycle Propagation, Memory, and Prediction: Insights from a century of magnetic proxies" 6164: 5923: 5883: 5814: 5767: 5736: 5341: 5322: 5304: 5199: 5077: 4819: 4684: 4571: 4520: 4322: 4195: 4146: 4042: 3785: 3741: 3589: 3380: 3319: 3270: 3219: 3154: 3043: 2984: 2677: 2659: 2549: 2399: 2288: 2257: 2159: 2129:"Unusual activity of the Sun during recent decades compared to the previous 11,000 years" 1936: 1903: 1726: 1657: 1474: 1417: 1375: 941: 913: 885: 775: 660: 628: 619: 473: 343: 189: 6962:

Willson, Richard C.; H.S. Hudson (1991). "The Sun's luminosity over a complete solar cycle".

2916:

Willson, Richard C.; H.S. Hudson (1991). "The Sun's luminosity over a complete solar cycle".

265:

Between 1645 and 1715, very few sunspots were observed and recorded. This was first noted by

8209: 7440: 7349: 7255: 7114: 7055: 7016: 6979: 6942: 6893: 6885: 6825: 6770: 6760: 6721: 6668: 6621: 6617: 6569: 6518: 6495:

Muñoz-Jaramillo, Andrés; Dasi-Espuig, María; Balmaceda, Laura A.; DeLuca, Edward E. (2013).

6475: 6424: 6373: 6241: 6204: 6094: 6075:"Surface warming by the solar cycle as revealed by the composite mean difference projection" 6045: 5985: 5948: 5940: 5851: 5806: 5798: 5709: 5662: 5613: 5594:"Can cosmic rays affect cloud condensation nuclei by altering new particle formation rates?" 5572: 5531: 5486: 5447: 5427: 5423: 5374: 5312: 5296: 5191: 5120: 5069: 5032: 5028: 4991: 4987: 4932: 4883: 4811: 4774: 4770: 4727: 4674: 4666: 4616: 4612: 4563: 4512: 4471: 4420: 4416: 4379: 4314: 4259: 4185: 4136: 4128: 4034: 3995: 3939: 3935: 3892: 3815: 3761: 3711: 3641: 3581: 3528: 3469: 3372: 3309: 3262: 3245:

Babcock, Horace W.; Babcock, Harold D. (March 1955). "The Sun's Magnetic Field, 1952–1954".

3211: 3207: 3146: 3142: 3089: 3085: 3033: 2976: 2933: 2877: 2799: 2667: 2649: 2539: 2529: 2464: 2416: 2351: 2305: 2249: 2151: 2095: 2091: 2037: 2033: 1920: 1820: 1746: 1145: 1122: 1038:, sometimes known as solar cosmic rays. These can cause radiation damage to electronics and 636: 266: 205: 87: 5138:"The Effect of 10.7 cm Solar Radiation on 2.4 GHz Digital Spread Spectrum Communications". 7674: 7654: 7629: 7524: 7469: 7445: 7322: 7158: 6329: 3965: 3681: 2434: 2213: 2058: 1779: 1560: 1518: 1280: 917: 853: 624: 600: 486: 427: 388: 270: 91: 44: 4292:"Unusual activity of the Sun during recent decades compared to the previous 11,000 years" 3509:

Sonett, C. P.; Finney, S. A.; Berger, A. (24 April 1990). "The Spectrum of Radiocarbon".

3406: 1988: 1496: 1314:

Speculations about the effects of cosmic-ray changes over the cycle potentially include:

7134: 7051: 7012: 6975: 6938: 6881: 6821: 6717: 6664: 6565: 6471: 6420: 6237: 6200: 6090: 6041: 5981: 5936: 5847: 5705: 5658: 5609: 5568: 5527: 5472: 5370: 5292: 5177: 5116: 5065: 4928: 4879: 4807: 4723: 4662: 4559: 4508: 4467: 4375: 4310: 4291: 4255: 4181: 4124: 3991: 3888: 3811: 3757: 3707: 3637: 3577: 3524: 3465: 3368: 3305: 3258: 3029: 2972: 2929: 2645: 2525: 2460: 2412: 2347: 2301: 2245: 2147: 2128: 1916: 1816: 1306:

10.7 cm solar flux could interfere with point-to-point terrestrial communications.

1194: 8154: 8148: 8120: 8114: 8097: 8091: 8074: 8068: 8051: 8045: 8028: 8022: 7994: 7977: 7971: 7954: 7644: 7624: 7619: 7407: 7312: 6898: 6855: 6775: 6748: 5317: 5276: 5209: 2672: 2619: 2468: 1443: 1428: 1421: 1156: 664: 585: 567: 544: 512: 499: 396: 347: 79: 50: 7076: 6574: 6539: 6523: 6496: 6480: 6445: 5855: 5275:

Kumar, Vinay; Dhaka, Surendra K.; Hitchman, Matthew H.; Yoden, Shigeo (6 March 2023).

4913:"ACRIM-gap and TSI trend issue resolved using a surface magnetic flux TSI proxy model" 2490: 1750: 8267: 7948: 7931: 7925: 7908: 7871: 7865: 7848: 7842: 7825: 7689: 7684: 7659: 7588: 7578: 7499: 7494: 7489: 7392: 7369: 7354: 6954: 6837: 6583: 6140: 6124: 5997: 5869: 5721: 5432: 5407: 5089: 4532: 4007: 3843: 3829: 3723: 3540: 3496: 3392: 3331: 3231: 3166: 3101: 2544: 2363: 2317: 1832: 1754: 1708: 1565: 1548: 1540: 1514: 1356: 816: 771: 746: 573: 356: 321: 313: 177: 173: 111: 107: 7067: 6733: 6680: 6378: 6351: 6121: 6108: 6059: 5627: 5386: 4897: 4628: 4273: 4064: 3999: 3951: 3653: 3483: 3181: 3116: 3002:

Chatzistergos, Theodosios; Krivova, Natalie A.; Ermolli, Ilaria (17 November 2022).

2476: 2355: 2269: 2062: 1948: 371: 30:

This article is about the sunspot cycle. For the 28-year cycle of the calendar, see

17: 8221: 7762: 7669: 7639: 7634: 7595: 7425: 7420: 7397: 7379: 7359: 7151: 6991: 4946: 4739: 4696: 4546:

Willson, R.C.; et al. (1981). "Observations of Solar Irradiance Variability".

4334: 4287: 3601: 3474: 3449: 2945: 2217: 2171: 2124: 2107: 1898: 1584: 1534: 1522: 1439: 1259: 1227: 1223: 1179: 1104: 1076: 873: 861: 857: 750: 708: 641: 384: 103: 6626: 6540:"The Discovery of Solar-like Activity Cycles Beyond the End of the Main Sequence?" 4996: 4961: 4710:

Willson RC; Hudson HS (1991). "The Sun's luminosity over a complete solar cycle".

4620: 3943: 3215: 3150: 3093: 2574: 2253: 2041: 1924: 1687: 7087: 5073: 5037: 5012: 4815: 4567: 3117:"Scrutinising the relationship between plage areas and sunspot areas and numbers" 2980: 2099: 7605: 7552: 7547: 7534: 7519: 7504: 7387: 7341: 5490: 1604:

A 2012 paper proposed that the torque exerted by the planets on a non-spherical

1413: 1363: 1215: 1183: 1149: 1129: 1088: 1072:

Gleißberg developed a CME forecasting method that relies on consecutive cycles.

893: 865: 834: 762: 754: 735: 712: 674: 288:

and Spörer independently noted the phenomena of sunspots appearing at different

259: 255: 220: 99: 7886: 6829: 5893: 5300: 5159:"Atmospheric Ionization and Clouds as Links Between Solar Activity and Climate" 3376: 3314: 3289: 3182:"Recovering the unsigned photospheric magnetic field from Ca II K observations" 3038: 3003: 2654: 996: 782:

events shows a strong solar cycle variation, peaking close to sunspot maximum.

695: 679: 330:

Leading polarities in both hemispheres flip from one sunspot cycle to the next.

7679: 7509: 7317: 7307: 6946: 6725: 6672: 6209: 6184: 5989: 5713: 4779: 4754: 4425: 4400: 4190: 4165: 4038: 3897: 3872: 3715: 3645: 1824: 1605: 1593: 1589: 1580: 1556: 1484: 1409: 1401: 1300: 1263: 1133: 1043: 1039: 392: 379:

Sunspot numbers over the past 11,400 years have been reconstructed using

243: 239: 39: 5790: 5775: 5667: 5642: 5308: 5251:"CERN's CLOUD experiment provides unprecedented insight into cloud formation" 4524: 4199: 4150: 4046: 3424: 3384: 3323: 3274: 3223: 3158: 3047: 2663: 2553: 1355:

The impact of the solar cycle on living organisms has been investigated (see

530:

Several lists of proposed historical "grand minima" of solar activity exist.

7562: 7435: 6259: 5810: 5342:"On climate response to changes in the cosmic ray flux and radiative budget" 5124: 1451: 1436: 1291: 1100: 1054: 948: 881: 877: 869: 380: 7188:

Science Briefs: Do Variations in the Solar Cycle Affect Our Climate System?

6907: 6784: 5953: 5771: 5326: 4823: 4688: 4679: 4644:"An influence of solar spectral variations on radiative forcing of climate" 4575: 4384: 4349: 4326: 3593: 3532: 2988: 2681: 2534: 2509: 2261: 2163: 1940: 5081: 4290:; Usoskin, Ilya G.; Kromer, Bernd; Schüssler, Manfred; Beer, Jürg (2004). 3558: 2127:; Usoskin, Ilya G.; Kromer, Bernd; Schüssler, Manfred; Beer, Jürg (2004). 2063:"Grand minima and maxima of solar activity: New observational constraints" 7704: 7042: 6765: 6099: 6074: 6050: 6025: 5618: 5593: 5577: 5552: 5378: 4937: 4912: 4888: 4863: 4516: 4476: 4441: 4264: 4229: 4132: 3820: 3766: 2236: 1667: 1652: 1609: 1425: 1330: 1137: 7197: 6889: 5916:"Solar forcing of winter climate variability in the Northern Hemisphere" 5361: 5052:

Haigh, J D (17 May 1996). "The Impact of Solar Variability on Climate".

4841: 4670: 4318: 4141: 3585: 2155: 689: 7364: 6264: 2379:"Rock layers show our sun has been in same cycle for 700 million years" 1932: 1395: 1359:). Some researchers claim to have found connections with human health. 1222:(EUV) and above. However, hotter upper layers of the Sun's atmosphere ( 1035: 1010: 614: 247: 235: 214: 95: 83: 5877: 2856:"What's wrong with the Sun? (Nothing) more information: Spotless Days" 1555:

quadrupolar field, generated through differential rotation within the

199: 7174: 6983: 5944: 5553:"Solar influences on cosmic rays and cloud formation: A reassessment" 4731: 4642:

Haigh, J. D; Winning, A. R; Toumi, R; Harder, J. W (6 October 2010).

2937: 2823: 2420: 2309: 1469:

Three proposed mechanisms mediate solar variations' climate impacts:

1379: 1242: 1199: 352: 126: 7202: 6915:

Usoskin, Ilya (2017). "A history of solar activity over millennia".

5195: 837:

over an odd solar cycle to exceed that of the preceding even cycle.

761:(CME). Flares consist of an abrupt emission of energy (primarily at 8216: 7164: 7059: 7020: 6872: 6812: 6708: 6556: 6429: 6394: 6368: 6245: 5229: 4978: 4366: 3982: 3926: 3450:"The Relation between the Amplitude and the Period of Solar Cycles" 3359: 3266: 3198: 3133: 3076: 3020: 2636: 2024: 1807: 1166:

Energy changes in UV irradiance involved in production and loss of

7217: 6929: 6655: 6513: 6462: 6411: 6011: 5802: 5696: 4603: 4458: 4246: 3802: 3698: 2451: 2082: 1367: 1251: 1238: 1237:

The photo montage to the left illustrates this variation for soft

1193: 1167: 995: 962: 927: 793: 766: 716: 688: 673: 618: 401: 370: 153: 49: 38: 4350:"Magnitudes and timescales of total solar irradiance variability" 3004:"Full-disc Ca ii K observations—A window to past solar magnetism" 1707:

This article incorporates text from this source, which is in the

1543:, which corresponds to an oscillatory exchange of energy between 1057:

on a space mission who are outside the shielding produced by the

833:

The Gnevyshev–Ohl rule describes the tendency for the sum of the

7699: 7191: 7178: 6325: 5254: 4864:"Secular total solar irradiance trend during solar cycles 21–23" 1207: 656: 555: 7777: 7773: 7251: 7207: 6393:

Yeates, Anthony R.; Nandy, Dibyendu; Mackay, Duncan H. (2008).

6024:

Zanchettin, D.; Rubino, A.; Traverso, P.; Tomasino, M. (2008).

1539:

The 11-year solar cycle is thought to be one-half of a 22-year

7278: 6291: 4063:, pp. 360–388, University of Arizona Press, Tucson AZ (1991). 1662: 1506:

is that solar variations only play a marginal role in driving

1295: 1171: 974:

Hallstatt ~2.5-kyr), cumulatively explain ~4.0% (δD), 2.9% (CO

147:

is that solar variations only play a marginal role in driving

75: 6309:

http://www.cnn.com/2001/TECH/space/02/16/sun.flips/index.html

1326:

A change in cosmic rays could affect certain types of clouds.

876:

cosmogenic isotopes stored in terrestrial reservoirs such as

860:, associated centennial variations in magnetic fields in the 230:

The idea of a cyclical solar cycle was first hypothesized by

6012:

Long-term solar activity influences on South American rivers

2771:"As the Sun Awakens, NASA Keeps a Wary Eye on Space Weather" 7242: 5797:. Washington DC: National Academies Press. pp. 66–68. 5226:"Department of Physics – the University of Texas at Dallas" 1262:, and increases in ionizing radiation significantly affect 7247: 5537:

10.1130/1052-5173(2003)013<0004:CDOPC>2.0.CO;2

1756:

Climate Change 2001: Working Group I: The Scientific Basis

944:) is hypothesized to extend for approximately 2,400 years. 2899:"NASA – Sun-Earth Day – Technology Through Time – Greece" 1400:

Skywave modes of radio communication operate by bending (

395:

is estimated to be 10.62 years and similarly in the

172:

Solar cycles have an average duration of about 11 years.

5741:

30TH INTERNATIONAL COSMIC RAY CONFERENCE, Merida, Mexico

1881:

Mittheilungen der Naturforschenden Gesellschaft in Bern

375:

Reconstruction of solar activity over 11,400 years

94:

and ejection of solar material, the number and size of

7227: 5011:

Solanki SK, Schuessler M, Fligge M (1 February 2002).

3684:(2017). "A History of Solar Activity over Millennia". 3617:"What the Sunspot Record Tells Us About Space Climate" 2618:

Bhowmik, Prantika; Nandy, Dibyendu (6 December 2018).

8193: 1286:

Sunspot activity has a major effect on long distance

1001:

correlation in amplitudes is variable to some degree.

7121:

Solanki, S.K.; Fligge, M. (2001). Wilson, A. (ed.).

5791:"Solar Variations, Ozone, and the Middle Atmosphere" 4440:

Krivova NA, Solanki SK, Wenzler T (1 October 2009).

4021:

Damon, Paul E.; Jirikowic, John L. (31 March 2006).

2596:"ADS search for "solar sunspot cycle 25 prediction"" 1853:[Observations of the sun in the year 1843]. 8141: 8134: 8107: 8084: 8061: 8038: 8015: 8008: 7987: 7964: 7941: 7918: 7901: 7894: 7858: 7835: 7818: 7811: 7727: 7713: 7571: 7533: 7468: 7406: 7378: 7340: 7331: 7298: 6599:"Is there a planetary influence on solar activity?" 3448:Du, Zhan-Le; Wang, Hua-Ning; He, Xiang-Tao (2006). 1749:; Ding, Y.; Griggs, D.J.; Noguer, M., eds. (2001). 281:who extensively researched this peculiar interval. 6260:"NASA Satellites Capture Start of New Solar Cycle" 6183:Molaverdikhani, Karan; Ajabshirizadeh, A. (2016). 4107:Past Interglacials Working Group of PAGES (2016). 3290:"Extreme Space-Weather Events and the Solar Cycle" 2061:; Solanki, Sami K.; Kovaltsov, Gennady A. (2007). 3512:Philosophical Transactions of the Royal Society A 1966: 1964: 1962: 1960: 1958: 1099:. Fission products include radionuclides such as 591:805 days had no sunspots during this cycle. 4755:"ACRIM3 and the Total Solar Irradiance database" 4401:"ACRIM3 and the Total Solar Irradiance database" 4023:"The Sun as a low-frequency harmonic oscillator" 2715:"SOHO: the new solar cycle starts with a 'bang'" 2185:"11,000 Year Sunspot Number Reconstruction" 1198:A solar cycle: a montage of ten years' worth of 940:The Hallstatt cycle (named after a cool and wet 5739:(June 2007). "Cosmic Rays and Global Warming". 5168:. Geophysical monograph series. Vol. 141. 2281: 2279: 2119: 2117: 1773:Assessment Report-4, Working group 1, chapter 2 1234:and X-ray flux varies markedly over the cycle. 5013:"Secular variation of the Sun's magnetic flux" 4838:"Total Solar Irradiance Graph from ACRIM page" 3615:Hathaway, David H.; Wilson, Robert M. (2004). 3407:"The Most Powerful Solar Flares Ever Recorded" 2491:"Centuries-old sketches solve sunspot mystery" 1741: 1739: 106:all exhibit a synchronized fluctuation from a 90:. Over the period of a solar cycle, levels of 7789: 7263: 5452:"Influence of Cosmic Rays on Earth's Climate" 3454:Chinese Journal of Astronomy and Astrophysics 1279:emission. F10.7 is often expressed in SFU or 320:In the same heliographic hemisphere, bipolar 307:The cycle's physical basis was elucidated by 284:In the second half of the nineteenth century 74:, is a nearly periodic 11-year change in the 8: 7086:Yaskell, Steven Haywood (31 December 2012). 6444:Karak, Bidya Binay; Nandy, Dibyendu (2012). 6137:"Sunspot activity may be linked to rainfall" 5166:Solar Variability and its Effects on Climate 4497:Journal of Geophysical Research: Atmospheres 2053: 2051: 1864: 1442:. These users occupy frequencies within the 696:http://solarcyclescience.com/solarcycle.html 680:http://solarcyclescience.com/solarcycle.html 6010:Pablo J.D. Mauas & Andrea P. Buccino. " 5641:Snow-Kropla, E.; et al. (April 2011). 2565: 2563: 1633:Formation and evolution of the Solar System 1521:(LEO) by altering the density of the upper 1329:It was proposed that, particularly at high 932:2,300 year Hallstatt solar variation cycles 8138: 8012: 7898: 7815: 7796: 7782: 7774: 7337: 7270: 7256: 7248: 5512:"Celestial driver of Phanerozoic climate?" 4354:Journal of Space Weather and Space Climate 3871:Vasiliev, S. S.; Dergachev, V. A. (2002). 3552: 3550: 2804:NOAA / NWS Space Weather Prediction Center 2700:NOAA / NWS Space Weather Prediction Center 2613: 2611: 1034:) produce a radiation flux of high-energy 7041: 6928: 6897: 6871: 6811: 6774: 6764: 6707: 6654: 6625: 6573: 6555: 6522: 6512: 6479: 6461: 6428: 6410: 6377: 6367: 6350:Hazra, Soumitra; Nandy, Dibyendu (2016). 6208: 6098: 6049: 5952: 5695: 5666: 5617: 5576: 5535: 5480: 5431: 5360: 5316: 5185: 5036: 4995: 4977: 4936: 4887: 4778: 4678: 4602: 4491:Amdur, T.; Huybers, P. (16 August 2023). 4475: 4457: 4424: 4383: 4365: 4263: 4245: 4189: 4140: 4109:"Interglacials of the last 800,000 years" 3981: 3925: 3896: 3819: 3801: 3765: 3697: 3473: 3358: 3313: 3197: 3132: 3075: 3037: 3019: 3008:Frontiers in Astronomy and Space Sciences 2671: 2653: 2635: 2543: 2533: 2450: 2235: 2081: 2023: 1844: 1842: 1806: 1761:Intergovernmental Panel on Climate Change 6122:Sunspot activity impacts on crop success 5510:Shaviv, Nir J & Veizer, Ján (2003). 5408:"Cosmoclimatology: a new theory emerges" 4840:. ACRIM project web page. Archived from 1241:, as observed by the Japanese satellite 409: 43:400 year sunspot history, including the 8200: 5164:. In Pap, Judit M.; Fox, Peter (eds.). 5157:Tinsley, Brian A.; Yu, Fangqun (2004). 2329: 2327: 1721: 1719: 1717: 1679: 1218:emits a proportion of radiation in the 942:period in Europe when glaciers advanced 774:. Consequently, the occurrence of both 730:Solar flares and coronal mass ejections 324:tend to have the same leading polarity. 3784:Owens M.J. & Forsyth R.J. (2013). 1504:scientific consensus on climate change 1487:changes, which may affect cloud cover. 884:and by using historic observations of 647:The best information today comes from 644:associated with large sunspot groups. 292:at different parts of the cycle. (See 145:scientific consensus on climate change 114:back to a period of minimum activity. 7228:Solar Influences Data Analysis Center 7123:Long-term changes in solar irradiance 4862:Willson R.C.; Mordvinov A.V. (2003). 4217:(in German). Berlin: Ahademie Verlag. 3499:, 1939, Astron. Mitt. Zurich, 14, 439 2696:"Solar Cycle 25 Preliminary Forecast" 1993:Solar Influences Data Analysis Center 1046:. Solar proton events also can cause 234:based on his regular observations of 140:phenomena elsewhere in the universe. 27:Periodic change in the Sun's activity 7: 6073:C. D. Camp & K. K. Tung (2007). 1901:(June 1976). "The Maunder Minimum". 721:Solar plage area evolution over time 262:, which continues to be used today. 238:made between 1761 and 1776 from the 5684:Meteorology and Atmospheric Physics 2377:Michael Marshall (18 August 2018). 1851:"Sonnenbeobachtungen im Jahre 1843" 1638:List of articles related to the Sun 1600:Speculated influence of the planets 1541:Babcock–Leighton solar dynamo cycle 1294:bands although medium wave and low 411:Major events and approximate dates 342:In 1961 the father-and-son team of 8182: 7152:Recent Total Solar Irradiance data 6538:Route, Matthew (20 October 2016). 6295:. 16 February 2001. Archived from 5789:National Research Council (1994). 4911:Scafetta N.; Willson R.C. (2009). 4399:Richard C. Willson (16 May 2014). 4083:Introduction to Quaternary Ecology 2713:Bernhard Fleck (14 January 2008). 1214:With a temperature of 5870 K, the 25: 7115:Solar Variability Affecting Earth 6544:The Astrophysical Journal Letters 6501:The Astrophysical Journal Letters 6320:Phillips, T. (15 February 2001). 5874:"Changing Sun, Changing Climate?" 5795:Solar Influences on Global Change 5647:Atmospheric Chemistry and Physics 4230:"Solar Modulation of Cosmic Rays" 3786:"The Heliospheric Magnetic Field" 2739:Tony Phillips (10 January 2008). 1513:Solar variations also affect the 1170:have atmospheric effects. The 30 363:solar magnetic field components. 163:Evolution of magnetism on the Sun 78:'s activity measured in terms of 8251: 8239: 8227: 8215: 8203: 7885: 7758: 7757: 7213:Windows to the Universe: The Sun 6597:José Abreu; et al. (2012). 5433:10.1111/j.1468-4004.2007.48118.x 4215:Die Häufigkeit der Sonnenflecken 3429:National Geophysical Data Center 1976:Living Reviews in Solar Physics, 1702: 1342:do not show any induced clouds. 273:after the wife-and-husband team 213: 198: 8183:List of solar maxima and minima 7235:Solar Cycle Update: Twin Peaks? 6917:Living Reviews in Solar Physics 6860:Living Reviews in Solar Physics 6753:Living Reviews in Solar Physics 6030:Journal of Geophysical Research 5879:The Discovery of Global Warming 5557:Journal of Geophysical Research 5349:Journal of Geophysical Research 4234:Living Reviews in Solar Physics 4000:10.1016/j.earscirev.2016.09.004 3790:Living Reviews in Solar Physics 3746:Living Reviews in Solar Physics 3686:Living Reviews in Solar Physics 2874:"Solaemon's Spotless Days Page" 2356:10.1016/j.precamres.2018.07.018 1731:Living Reviews in Solar Physics 1727:The Sun and the Earth's Climate 552:Space Weather Prediction Center 7198:Yohkoh Public Outreach Project 6163:, Cambridge University Press, 5592:Pierce, J.; Adams, P. (2009). 4759:Astrophysics and Space Science 4405:Astrophysics and Space Science 3425:"Extreme Space Weather Events" 2189:Global Change Master Directory 1053:CME radiation is dangerous to 952:modulates the 208-year period. 651:(a cooperative project of the 1: 7740:List of heliophysics missions 7243:SunSpotWatch.com (since 1999) 5856:10.1016/S0273-1177(01)00270-8 5551:Sun, B.; Bradley, R. (2002). 5516:Geological Society of America 2824:"Sunspot Number | SILSO" 2769:Tony Phillips (4 June 2010). 2254:10.1103/PhysRevLett.91.211101 1925:10.1126/science.192.4245.1189 1733:(access date 31 January 2012) 1688:"NASA/Marshall Solar Physics" 1483:Solar wind-mediated galactic 956:Brückner-Egeson-Lockyer cycle 64:solar magnetic activity cycle 7745:Category:Missions to the Sun 7183:Marshall Space Flight Center 7113:NOAA / NESDIS / NGDC (2002) 6606:Astronomy & Astrophysics 6079:Geophysical Research Letters 5882:. Harvard University Press. 5598:Geophysical Research Letters 5074:10.1126/science.272.5264.981 4816:10.1126/science.211.4483.700 4753:Willson, Richard C. (2014). 4591:Astronomy & Astrophysics 4568:10.1126/science.211.4483.700 4446:Geophysical Research Letters 3186:Astronomy & Astrophysics 3121:Astronomy & Astrophysics 2981:10.1126/science.211.4483.700 2741:"Solar Cycle 24 begins" 2497:. 1 August 2009. p. 10. 2469:10.1088/0004-637X/700/2/L154 2012:Astronomy & Astrophysics 1997:Royal Observatory of Belgium 1266:-influenced temperature and 663:, where the solar "surface" 112:period of a maximum activity 6627:10.1051/0004-6361/201219997 6575:10.3847/2041-8205/830/2/L27 6524:10.1088/2041-8205/767/2/L25 6481:10.1088/2041-8205/761/1/L13 5491:10.1103/PhysRevLett.81.5027 4997:10.1051/0004-6361/202141516 4621:10.1051/0004-6361/201423628 4213:Wolfgang Gleißberg (1953). 4170:Quaternary Science Advances 3944:10.1051/0004-6361/201527295 3216:10.1051/0004-6361/201935131 3151:10.1051/0004-6361/202244913 3094:10.1051/0004-6361/202037746 2042:10.1051/0004-6361/201832956 1454:usable for communications. 8295: 7165:N0NBH Solar data and tools 7078:Sunspots and Their Effects 6830:10.1007/s11207-023-02167-w 6287:"Sun flips magnetic field" 6189:Advances in Space Research 5836:Advances in Space Research 5760:Neuroendocrinology Letters 5412:Astronomy & Geophysics 5406:Svensmark, Henrik (2007). 5301:10.1038/s41598-023-30447-9 5170:American Geophysical Union 5038:10.1051/0004-6361:20011790 5017:Astronomy and Astrophysics 4966:Astronomy and Astrophysics 4061:In The Sun in Time, Vol. 1 3377:10.1007/s11207-022-02037-x 3315:10.1007/s11207-021-01831-3 3064:Astronomy and Astrophysics 3039:10.3389/fspas.2022.1038949 2655:10.1038/s41467-018-07690-0 2100:10.1051/0004-6361:20077704 1532: 1393: 1190:Short-wavelength radiation 1120: 1079:to re-enter more quickly. 1061:. Future mission designs ( 826: 733: 706: 612: 598: 583: 565: 542: 187: 108:period of minimum activity 82:in the number of observed 29: 8168: 7883: 7753: 7721:G-type main-sequence star 7285: 6947:10.1007/s41116-017-0006-9 6726:10.1007/s11207-019-1447-1 6673:10.1007/s11207-014-0475-0 6450:The Astrophysical Journal 6399:The Astrophysical Journal 6379:10.3847/0004-637X/832/1/9 6356:The Astrophysical Journal 6226:The Astrophysical Journal 6210:10.1016/j.asr.2016.05.035 5990:10.1191/0959683603hl623rp 5714:10.1007/s00703-013-0260-x 4780:10.1007/s10509-014-1961-4 4426:10.1007/s10509-014-1961-4 4191:10.1016/j.qsa.2021.100037 4039:10.2458/azu_js_rc.34.1450 3898:10.5194/angeo-20-115-2002 3716:10.1007/s41116-017-0006-9 3646:10.1007/s11207-005-3996-8 3247:The Astrophysical Journal 2800:"Solar Cycle Progression" 2545:21.11116/0000-0003-2C5D-5 2439:The Astrophysical Journal 1989:"Sunspot Number graphics" 1855:Astronomische Nachrichten 1825:10.1007/s11207-019-1466-y 1473:Total solar irradiance (" 1450:, a limit on the highest 1406:electromagnetic radiation 1321:cloud condensation nuclei 924:Other hypothesized cycles 868:have been detected using 7584:In mythology and culture 7081:. New York: McGraw Hill. 6854:Hathaway, David (2015). 6749:"Solar Cycle Prediction" 5668:10.5194/acp-11-4001-2011 3475:10.1088/1009-9271/6/4/12 2571:National Weather Service 1448:maximum usable frequency 1372:continuously regenerated 1083:Galactic cosmic ray flux 819:who first described it. 780:solar energetic particle 269:and was later named the 7175:Solar Physics Web Pages 7092:. Trafford Publishing. 6618:2012A&A...548A..88A 5460:Physical Review Letters 5424:2007A&G....48a..18S 5146:(3). July–October 1999. 5125:10.1029/JD092iD01p00829 5029:2002A&A...383..706S 4988:2021A&A...656A.104C 4771:2014Ap&SS.352..341W 4613:2014A&A...570A..85Y 4417:2014Ap&SS.352..341W 4067:(accessed 16 July 2015) 3936:2016A&A...587A.150U 3208:2019A&A...626A.114C 3143:2022A&A...667A.167C 3086:2020A&A...639A..88C 2223:Physical Review Letters 2092:2007A&A...471..301U 2034:2018A&A...620A.120W 1433:amateur radio operators 1366:. In the stratosphere, 1268:electrical conductivity 1260:stratospheric chemistry 958:(30 to 40 year cycles). 252:Samuel Heinrich Schwabe 206:Samuel Heinrich Schwabe 7451:Supra-arcade downflows 7190:. By David Rind, NASA 7075:Stetson, H.T. (1937). 6143:, 8 Nov., 2008, p. 10. 5340:Shaviv, Nir J (2005). 4348:Kopp G (1 July 2016). 4228:Potgeiter, M. (2013). 3851:U.S. Geological Survey 3533:10.1098/rsta.1990.0022 2575:"Hello Solar Cycle 25" 2535:10.5194/cp-14-687-2018 1865: 1290:, particularly on the 1211: 1059:Earth's magnetic field 1032:coronal mass ejections 1002: 933: 799: 759:coronal mass ejections 722: 699: 683: 632: 407: 376: 290:heliographic latitudes 164: 55: 47: 32:Solar cycle (calendar) 8151:(2008 Dec – 2019 Dec) 8123:(1996 Aug – 2008 Dec) 8117:(1986 Sep – 1996 Aug) 8100:(1976 Mar – 1986 Sep) 8094:(1964 Oct – 1976 Mar) 8077:(1954 Apr – 1964 Oct) 8071:(1944 Feb – 1954 Apr) 8054:(1933 Sep – 1944 Feb) 8048:(1923 Aug – 1933 Sep) 8031:(1913 Jul – 1923 Aug) 8025:(1902 Jan – 1913 Jul) 7997:(1890 Mar – 1902 Jan) 7980:(1878 Dec – 1890 Mar) 7974:(1867 Mar – 1878 Dec) 7957:(1855 Dec – 1867 Mar) 7951:(1843 Jul – 1855 Dec) 7934:(1833 Nov – 1843 Jul) 7928:(1823 May – 1833 Nov) 7911:(1810 Aug – 1823 May) 7874:(1798 Apr – 1810 Aug) 7868:(1784 Sep – 1798 Apr) 7851:(1775 Jun – 1784 Sep) 7845:(1766 Jun – 1775 Jun) 7828:(1755 Feb – 1766 Jun) 7431:Coronal mass ejection 7203:Stanford Solar Center 7030:Astrophysical Journal 7001:Astrophysical Journal 6322:"The Sun Does a Flip" 4113:Reviews of Geophysics 3970:Earth-Science Reviews 3844:"The Sun and Climate" 2719:European Space Agency 2624:Nature Communications 1545:toroidal and poloidal 1508:global climate change 1197: 999: 931: 797: 740:Coronal mass ejection 720: 698:solarcyclescience.com 692: 682:solarcyclescience.com 677: 653:European Space Agency 627:in the Chronicles of 622: 405: 374: 361:toroidal and poloidal 279:Edward Walter Maunder 184:Observational history 162: 149:global climate change 53: 42: 8178:List of solar storms 8173:List of solar cycles 8157:(2019 Dec – present) 7695:Standard solar model 7665:Solar radio emission 7483:List of solar cycles 7161:updated every Monday 6766:10.12942/lrsp-2010-6 6747:K. Petrovay (2019). 6100:10.1029/2007GL030207 6051:10.1029/2007JD009157 5619:10.1029/2009gl037946 5578:10.1029/2001jd000560 5379:10.1029/2004JA010866 5172:. pp. 321–339. 4938:10.1029/2008GL036307 4889:10.1029/2002GL016038 4517:10.1029/2023JD038941 4477:10.1029/2009GL040707 4385:10.1051/swsc/2016025 4265:10.12942/lrsp-2013-3 4133:10.1002/2015RG000482 3853:. Fact Sheet 0095-00 3821:10.12942/lrsp-2013-5 3767:10.12942/lrsp-2013-4 3740:Lockwood M. (2013). 2903:sunearthday.nasa.gov 2336:Precambrian Research 1648:List of solar storms 1643:List of solar cycles 1288:radio communications 1175:atmospheric pressure 1097:spallation reactions 625:drawing of a sunspot 131:interplanetary space 62:, also known as the 18:Solar system warming 7515:Magnetic switchback 7135:2000ESASP.463...51S 7052:2001ApJ...553..897D 7013:1977ApJ...215..952F 6976:1991Natur.351...42W 6939:2017LRSP...14....3U 6890:10.1007/lrsp-2015-4 6882:2015LRSP...12....4H 6822:2023SoPh..298...70C 6718:2019SoPh..294...60S 6665:2014SoPh..289.2333P 6566:2016ApJ...830L..27R 6472:2012ApJ...761L..13K 6421:2008ApJ...673..544Y 6238:1919ApJ....49..153H 6201:2016AdSpR..58..924M 6091:2007GeoRL..3414703C 6042:2008JGRD..11312102Z 5982:2003Holoc..13..311L 5937:2011NatGe...4..753I 5848:2001AdSpR..27.1983E 5706:2013MAP...121..137E 5659:2011ACP....11.4001S 5610:2009GeoRL..36.9820P 5569:2002JGRD..107.4211S 5528:2003GSAT...13g...4S 5473:1998PhRvL..81.5027S 5371:2005JGRA..110.8105S 5293:2023NatSR..13.3707K 5178:2004GMS...141..321T 5117:1987JGR....92..829T 5066:1996Sci...272..981H 4929:2009GeoRL..36.5701S 4880:2003GeoRL..30.1199W 4808:1981Sci...211..700W 4724:1991Natur.351...42W 4671:10.1038/nature09426 4663:2010Natur.467..696H 4560:1981Sci...211..700W 4509:2023JGRD..12838941A 4468:2009GeoRL..3620101K 4376:2016JSWSC...6A..30K 4319:10.1038/nature02995 4311:2004Natur.431.1084S 4256:2013LRSP...10....3P 4182:2021QSAdv...400037V 4164:Viaggi, P. (2021). 4125:2016RvGeo..54..162P 3992:2016ESRv..162...24S 3889:2002AnGeo..20..115V 3877:Annales Geophysicae 3812:2013LRSP...10....5O 3758:2013LRSP...10....4L 3708:2017LRSP...14....3U 3638:2004SoPh..224....5H 3586:10.1038/nature04121 3578:2005Natur.438..208B 3525:1990RSPTA.330..413S 3466:2006ChJAA...6..489D 3369:2022SoPh..297..105O 3306:2021SoPh..296...82O 3259:1955ApJ...121..349B 3030:2022FrASS...938949C 2973:1981Sci...211..700W 2930:1991Natur.351...42W 2646:2018NatCo...9.5209B 2526:2018CliPa..14..687C 2514:Climate of the Past 2461:2009ApJ...700L.154U 2413:2012NatGe...5..397M 2348:2018PreR..315...75L 2302:2017Geo....45..279L 2246:2003PhRvL..91u1101U 2156:10.1038/nature02995 2148:2004Natur.431.1084S 2142:(7012): 1084–1087. 1970:David H. Hathaway, 1917:1976Sci...192.1189E 1911:(4245): 1189–1202. 1817:2019SoPh..294...78K 1549:solar-cycle maximum 1416:. This affects the 1390:Radio communication 1220:extreme ultraviolet 659:), such as the MDI 412: 298:Alfred Harrison Joy 275:Annie S. D. Maunder 138:magnetohydrodynamic 8279:Periodic phenomena 7705:Sunlight radiation 7300:Internal structure 7157:2013-07-06 at the 6848:General references 6127:, 18 November 2004 5355:(A08105): A08105. 5281:Scientific Reports 4917:Geophys. Res. Lett 4868:Geophys. Res. Lett 1778:2013-12-07 at the 1618:The Jupiter Effect 1212: 1048:single-event upset 1003: 934: 829:Gnevyshev–Ohl rule 823:Gnevyshev–Ohl rule 800: 776:geomagnetic storms 723: 700: 684: 633: 410: 408: 377: 337:Gnevyshev-Ohl rule 309:George Ellery Hale 286:Richard Carrington 232:Christian Horrebow 165: 56: 48: 8191: 8190: 8164: 8163: 8130: 8129: 8004: 8003: 7881: 7880: 7771: 7770: 7735:Solar observatory 7650:Solar observation 7548:Termination shock 7464: 7463: 7416:Transition region 7144:978-92-9092-693-1 7099:978-1-4669-6300-9 6856:"The solar cycle" 6170:978-0-521-88009-1 5924:Nature Geoscience 5889:978-0-674-01157-1 5842:(12): 1983–1986. 5820:978-0-309-05148-4 5467:(22): 5027–5030. 5448:Svensmark, Henrik 5253:(Press release). 5205:978-0-87590-406-1 5060:(5264): 981–984. 3914:Astron. Astrophys 2400:Nature Geoscience 2070:Astron. Astrophys 1972:"The Solar Cycle" 1725:Joanna D. Haigh " 1658:Stellar evolution 1615:In 1974 the book 1475:Radiative forcing 1132:were launched on 1006:Surface magnetism 914:Hans Eduard Suess 886:geomagnetic storm 703:Faculae and plage 629:John of Worcester 524: 523: 451:Medieval maximum 190:Solar observation 160: 16:(Redirected from 8286: 8256: 8255: 8254: 8244: 8243: 8242: 8232: 8231: 8230: 8220: 8219: 8208: 8207: 8206: 8199: 8139: 8013: 7899: 7889: 7816: 7798: 7791: 7784: 7775: 7761: 7760: 7350:Supergranulation 7338: 7272: 7265: 7258: 7249: 7239: 7170:SolarCycle24.com 7148: 7103: 7082: 7071: 7045: 7043:astro-ph/0101473 7024: 6995: 6984:10.1038/351042a0 6958: 6932: 6911: 6901: 6875: 6842: 6841: 6815: 6795: 6789: 6788: 6778: 6768: 6744: 6738: 6737: 6711: 6691: 6685: 6684: 6658: 6638: 6632: 6631: 6629: 6603: 6594: 6588: 6587: 6577: 6559: 6535: 6529: 6528: 6526: 6516: 6492: 6486: 6485: 6483: 6465: 6441: 6435: 6434: 6432: 6414: 6390: 6384: 6383: 6381: 6371: 6347: 6341: 6340: 6338: 6337: 6328:. Archived from 6317: 6311: 6307: 6305: 6304: 6283: 6277: 6276: 6274: 6273: 6268:. 4 January 2008 6256: 6250: 6249: 6221: 6215: 6214: 6212: 6180: 6174: 6173: 6150: 6144: 6134: 6128: 6119: 6113: 6112: 6102: 6070: 6064: 6063: 6053: 6021: 6015: 6008: 6002: 6001: 5965: 5959: 5958: 5956: 5945:10.1038/ngeo1282 5920: 5911: 5905: 5904: 5902: 5901: 5892:. Archived from 5866: 5860: 5859: 5831: 5825: 5824: 5811:2060/19950005971 5786: 5780: 5779: 5774:. Archived from 5751: 5745: 5744: 5732: 5726: 5725: 5699: 5679: 5673: 5672: 5670: 5638: 5632: 5631: 5621: 5589: 5583: 5582: 5580: 5548: 5542: 5541: 5539: 5507: 5501: 5500: 5498: 5497: 5484: 5456: 5444: 5438: 5437: 5435: 5418:(1): 1.18–1.24. 5403: 5397: 5396: 5394: 5393: 5364: 5346: 5337: 5331: 5330: 5320: 5272: 5266: 5265: 5263: 5262: 5257:. 25 August 2011 5247: 5241: 5240: 5238: 5237: 5228:. Archived from 5223: 5221: 5220: 5214: 5208:. Archived from 5189: 5163: 5154: 5148: 5147: 5135: 5129: 5128: 5100: 5094: 5093: 5049: 5043: 5042: 5040: 5008: 5002: 5001: 4999: 4981: 4957: 4951: 4950: 4940: 4908: 4902: 4901: 4891: 4859: 4853: 4852: 4850: 4849: 4834: 4828: 4827: 4791: 4785: 4784: 4782: 4750: 4744: 4743: 4732:10.1038/351042a0 4707: 4701: 4700: 4682: 4648: 4639: 4633: 4632: 4606: 4586: 4580: 4579: 4543: 4537: 4536: 4488: 4482: 4481: 4479: 4461: 4437: 4431: 4430: 4428: 4396: 4390: 4389: 4387: 4369: 4345: 4339: 4338: 4305:(7012): 1084–7. 4296: 4288:Solanki, Sami K. 4284: 4278: 4277: 4267: 4249: 4225: 4219: 4218: 4210: 4204: 4203: 4193: 4161: 4155: 4154: 4144: 4104: 4098: 4097: 4095: 4094: 4085:. Archived from 4074: 4068: 4057: 4051: 4050: 4018: 4012: 4011: 3985: 3966:Scafetta, Nicola 3962: 3956: 3955: 3929: 3909: 3903: 3902: 3900: 3868: 3862: 3861: 3859: 3858: 3848: 3840: 3834: 3833: 3823: 3805: 3781: 3775: 3771: 3769: 3737: 3731: 3727: 3701: 3678: 3672: 3671: 3669: 3668: 3662: 3656:. Archived from 3621: 3612: 3606: 3605: 3572:(7065): 208–11. 3563: 3554: 3545: 3544: 3519:(1615): 413–26. 3506: 3500: 3494: 3488: 3487: 3477: 3445: 3439: 3438: 3436: 3435: 3421: 3415: 3414: 3411:Spaceweather.com 3403: 3397: 3396: 3362: 3342: 3336: 3335: 3317: 3285: 3279: 3278: 3242: 3236: 3235: 3201: 3177: 3171: 3170: 3136: 3112: 3106: 3105: 3079: 3058: 3052: 3051: 3041: 3023: 2999: 2993: 2992: 2956: 2950: 2949: 2938:10.1038/351042a0 2913: 2907: 2906: 2895: 2889: 2888: 2886: 2885: 2876:. Archived from 2870: 2864: 2863: 2858:. Archived from 2852: 2846: 2845: 2838: 2832: 2831: 2820: 2814: 2813: 2811: 2810: 2796: 2790: 2789: 2787: 2786: 2777:. Archived from 2766: 2760: 2759: 2757: 2756: 2747:. Archived from 2736: 2730: 2729: 2727: 2726: 2710: 2704: 2703: 2692: 2686: 2685: 2675: 2657: 2639: 2615: 2606: 2605: 2603: 2602: 2591: 2585: 2584: 2582: 2581: 2567: 2558: 2557: 2547: 2537: 2505: 2499: 2498: 2487: 2481: 2480: 2454: 2431: 2425: 2424: 2421:10.1038/ngeo1460 2393: 2387: 2386: 2374: 2368: 2367: 2331: 2322: 2321: 2310:10.1130/G38669.1 2283: 2274: 2273: 2239: 2237:astro-ph/0310823 2218:Solanki, Sami K. 2214:Usoskin, Ilya G. 2210: 2204: 2203: 2201: 2200: 2191:. Archived from 2181: 2179: 2178: 2133: 2125:Solanki, Sami K. 2121: 2112: 2111: 2085: 2067: 2059:Usoskin, Ilya G. 2055: 2046: 2045: 2027: 2007: 2001: 2000: 1985: 1979: 1968: 1953: 1952: 1895: 1889: 1888: 1876: 1870: 1868: 1863:From page 235: " 1862: 1849:Schwabe (1843). 1846: 1837: 1836: 1810: 1788: 1782: 1770: 1768: 1767: 1743: 1734: 1723: 1712: 1706: 1705: 1701: 1699: 1698: 1684: 1281:solar flux units 1274:Solar radio flux 1146:solar luminosity 1123:Solar irradiance 1117:Solar irradiance 852:As pioneered by 847:Gleissberg cycle 841:Gleissberg cycle 812:Waldmeier effect 806:Waldmeier effect 637:solar luminosity 413: 217: 202: 161: 21: 8294: 8293: 8289: 8288: 8287: 8285: 8284: 8283: 8264: 8263: 8262: 8252: 8250: 8240: 8238: 8228: 8226: 8214: 8204: 8202: 8194: 8192: 8187: 8160: 8155:Solar cycle 25 8149:Solar cycle 24 8126: 8121:Solar cycle 23 8115:Solar cycle 22 8103: 8098:Solar cycle 21 8092:Solar cycle 20 8080: 8075:Solar cycle 19 8069:Solar cycle 18 8057: 8052:Solar cycle 17 8046:Solar cycle 16 8034: 8029:Solar cycle 15 8023:Solar cycle 14 8000: 7995:Solar cycle 13 7983: 7978:Solar cycle 12 7972:Solar cycle 11 7960: 7955:Solar cycle 10 7937: 7914: 7890: 7877: 7854: 7831: 7807: 7802: 7772: 7767: 7749: 7723: 7709: 7675:Solar telescope 7655:Solar phenomena 7630:Solar astronomy 7567: 7529: 7525:Helioseismology 7460: 7446:Helmet streamer 7402: 7374: 7327: 7323:Convection zone 7294: 7281: 7276: 7232: 7159:Wayback Machine 7145: 7120: 7110: 7100: 7085: 7074: 7027: 6998: 6961: 6914: 6853: 6850: 6845: 6797: 6796: 6792: 6746: 6745: 6741: 6693: 6692: 6688: 6640: 6639: 6635: 6601: 6596: 6595: 6591: 6537: 6536: 6532: 6494: 6493: 6489: 6443: 6442: 6438: 6392: 6391: 6387: 6349: 6348: 6344: 6335: 6333: 6319: 6318: 6314: 6302: 6300: 6285: 6284: 6280: 6271: 6269: 6258: 6257: 6253: 6223: 6222: 6218: 6182: 6181: 6177: 6171: 6152: 6151: 6147: 6135: 6131: 6120: 6116: 6072: 6071: 6067: 6036:(D12): D12102. 6023: 6022: 6018: 6009: 6005: 5967: 5966: 5962: 5918: 5913: 5912: 5908: 5899: 5897: 5890: 5868: 5867: 5863: 5833: 5832: 5828: 5821: 5788: 5787: 5783: 5753: 5752: 5748: 5734: 5733: 5729: 5681: 5680: 5676: 5640: 5639: 5635: 5591: 5590: 5586: 5550: 5549: 5545: 5509: 5508: 5504: 5495: 5493: 5454: 5446: 5445: 5441: 5405: 5404: 5400: 5391: 5389: 5362:physics/0409123 5344: 5339: 5338: 5334: 5274: 5273: 5269: 5260: 5258: 5249: 5248: 5244: 5235: 5233: 5224: 5218: 5216: 5212: 5206: 5196:10.1029/141GM22 5187:10.1.1.175.5237 5161: 5156: 5155: 5151: 5137: 5136: 5132: 5111:(D1): 829–838. 5105:J. Geophys. Res 5102: 5101: 5097: 5051: 5050: 5046: 5010: 5009: 5005: 4959: 4958: 4954: 4910: 4909: 4905: 4861: 4860: 4856: 4847: 4845: 4836: 4835: 4831: 4802:(4483): 700–2. 4793: 4792: 4788: 4752: 4751: 4747: 4709: 4708: 4704: 4657:(7316): 696–9. 4646: 4641: 4640: 4636: 4588: 4587: 4583: 4554:(4483): 700–2. 4545: 4544: 4540: 4490: 4489: 4485: 4439: 4438: 4434: 4398: 4397: 4393: 4347: 4346: 4342: 4294: 4286: 4285: 4281: 4227: 4226: 4222: 4212: 4211: 4207: 4163: 4162: 4158: 4106: 4105: 4101: 4092: 4090: 4077: 4075: 4071: 4058: 4054: 4020: 4019: 4015: 3964: 3963: 3959: 3911: 3910: 3906: 3870: 3869: 3865: 3856: 3854: 3846: 3842: 3841: 3837: 3783: 3782: 3778: 3739: 3738: 3734: 3680: 3679: 3675: 3666: 3664: 3660: 3619: 3614: 3613: 3609: 3561: 3556: 3555: 3548: 3508: 3507: 3503: 3495: 3491: 3447: 3446: 3442: 3433: 3431: 3423: 3422: 3418: 3405: 3404: 3400: 3344: 3343: 3339: 3287: 3286: 3282: 3244: 3243: 3239: 3179: 3178: 3174: 3114: 3113: 3109: 3060: 3059: 3055: 3001: 3000: 2996: 2967:(4483): 700–2. 2958: 2957: 2953: 2915: 2914: 2910: 2897: 2896: 2892: 2883: 2881: 2872: 2871: 2867: 2854: 2853: 2849: 2842:"Spotless Days" 2840: 2839: 2835: 2822: 2821: 2817: 2808: 2806: 2798: 2797: 2793: 2784: 2782: 2768: 2767: 2763: 2754: 2752: 2738: 2737: 2733: 2724: 2722: 2721:(Press release) 2712: 2711: 2707: 2694: 2693: 2689: 2617: 2616: 2609: 2600: 2598: 2594: 2592: 2588: 2579: 2577: 2569: 2568: 2561: 2507: 2506: 2502: 2489: 2488: 2484: 2433: 2432: 2428: 2395: 2394: 2390: 2376: 2375: 2371: 2333: 2332: 2325: 2285: 2284: 2277: 2212: 2211: 2207: 2198: 2196: 2183: 2176: 2174: 2131: 2123: 2122: 2115: 2065: 2057: 2056: 2049: 2009: 2008: 2004: 1987: 1986: 1982: 1969: 1956: 1897: 1896: 1892: 1878: 1877: 1873: 1848: 1847: 1840: 1790: 1789: 1785: 1780:Wayback Machine 1765: 1763: 1745: 1744: 1737: 1724: 1715: 1703: 1696: 1694: 1686: 1685: 1681: 1677: 1672: 1628: 1602: 1561:Convection zone 1537: 1531: 1519:low Earth orbit 1460: 1404:) radio waves ( 1398: 1392: 1383: 1353: 1348: 1312: 1276: 1192: 1125: 1119: 1114: 1085: 1028: 1023: 1008: 994: 989: 981: 978:), and 6.6% (CH 977: 972: 968: 926: 918:Hessel de Vries 902: 854:Ilya G. Usoskin 843: 831: 825: 808: 792: 742: 734:Main articles: 732: 715: 707:Main articles: 705: 617: 611: 603: 601:Solar phenomena 597: 588: 582: 570: 564: 547: 541: 536: 487:Maunder Minimum 428:Homeric minimum 369: 271:Maunder minimum 242:observatory in 228: 227: 226: 225: 224: 218: 210: 209: 203: 192: 186: 170: 154: 92:solar radiation 45:Maunder Minimum 35: 28: 23: 22: 15: 12: 11: 5: 8292: 8290: 8282: 8281: 8276: 8266: 8265: 8261: 8260: 8248: 8236: 8224: 8212: 8189: 8188: 8186: 8185: 8180: 8175: 8169: 8166: 8165: 8162: 8161: 8159: 8158: 8152: 8145: 8143: 8136: 8132: 8131: 8128: 8127: 8125: 8124: 8118: 8111: 8109: 8105: 8104: 8102: 8101: 8095: 8088: 8086: 8082: 8081: 8079: 8078: 8072: 8065: 8063: 8059: 8058: 8056: 8055: 8049: 8042: 8040: 8036: 8035: 8033: 8032: 8026: 8019: 8017: 8010: 8006: 8005: 8002: 8001: 7999: 7998: 7991: 7989: 7985: 7984: 7982: 7981: 7975: 7968: 7966: 7962: 7961: 7959: 7958: 7952: 7949:Solar cycle 9 7945: 7943: 7939: 7938: 7936: 7935: 7932:Solar cycle 8 7929: 7926:Solar cycle 7 7922: 7920: 7916: 7915: 7913: 7912: 7909:Solar cycle 6 7905: 7903: 7896: 7892: 7891: 7884: 7882: 7879: 7878: 7876: 7875: 7872:Solar cycle 5 7869: 7866:Solar cycle 4 7862: 7860: 7856: 7855: 7853: 7852: 7849:Solar cycle 3 7846: 7843:Solar cycle 2 7839: 7837: 7833: 7832: 7830: 7829: 7826:Solar cycle 1 7822: 7820: 7813: 7809: 7808: 7803: 7801: 7800: 7793: 7786: 7778: 7769: 7768: 7766: 7765: 7754: 7751: 7750: 7748: 7747: 7742: 7737: 7731: 7729: 7725: 7724: 7719: 7717: 7715:Spectral class 7711: 7710: 7708: 7707: 7702: 7697: 7692: 7687: 7682: 7677: 7672: 7667: 7662: 7657: 7652: 7647: 7645:Solar neutrino 7642: 7637: 7632: 7627: 7625:Solar activity 7622: 7620:Sun in fiction 7617: 7616: 7615: 7614: 7613: 7598: 7593: 7592: 7591: 7586: 7575: 7573: 7569: 7568: 7566: 7565: 7560: 7555: 7550: 7545: 7539: 7537: 7531: 7530: 7528: 7527: 7522: 7517: 7512: 7507: 7502: 7497: 7492: 7487: 7486: 7485: 7474: 7472: 7466: 7465: 7462: 7461: 7459: 7458: 7456:Alfvén surface 7453: 7448: 7443: 7438: 7433: 7428: 7423: 7418: 7412: 7410: 7404: 7403: 7401: 7400: 7395: 7390: 7384: 7382: 7376: 7375: 7373: 7372: 7367: 7362: 7357: 7352: 7346: 7344: 7335: 7329: 7328: 7326: 7325: 7320: 7315: 7313:Radiation zone 7310: 7304: 7302: 7296: 7295: 7293: 7292: 7286: 7283: 7282: 7277: 7275: 7274: 7267: 7260: 7252: 7246: 7245: 7240: 7230: 7225: 7223:TRACE Web Site 7220: 7215: 7210: 7205: 7200: 7195: 7194:, January 2009 7185: 7172: 7167: 7162: 7149: 7143: 7118: 7109: 7108:External links 7106: 7105: 7104: 7098: 7083: 7072: 7060:10.1086/320976 7036:(2): 897–904. 7025: 7021:10.1086/155431 6996: 6970:(6321): 42–4. 6959: 6912: 6849: 6846: 6844: 6843: 6790: 6739: 6686: 6633: 6589: 6530: 6487: 6436: 6430:10.1086/524352 6385: 6342: 6312: 6278: 6251: 6246:10.1086/142452 6216: 6195:(6): 924–937. 6175: 6169: 6145: 6129: 6114: 6085:(14): L14703. 6065: 6016: 6003: 5960: 5906: 5888: 5870:Weart, Spencer 5861: 5826: 5819: 5781: 5778:on 2008-07-29. 5766:(3): 233–258. 5746: 5737:Wolfendale, A. 5727: 5674: 5633: 5584: 5543: 5502: 5482:10.1.1.522.585 5439: 5398: 5332: 5267: 5242: 5204: 5149: 5130: 5095: 5044: 5023:(2): 706–712. 5003: 4952: 4903: 4854: 4829: 4786: 4765:(2): 341–352. 4745: 4718:(6321): 42–4. 4702: 4634: 4581: 4538: 4483: 4452:(20): L20101. 4432: 4411:(2): 341–352. 4391: 4340: 4279: 4220: 4205: 4156: 4119:(1): 162–219. 4099: 4069: 4052: 4033:(2): 199–205. 4013: 3957: 3904: 3863: 3835: 3776: 3732: 3673: 3607: 3546: 3501: 3489: 3460:(4): 489–494. 3440: 3416: 3398: 3337: 3280: 3267:10.1086/145994 3237: 3172: 3107: 3053: 2994: 2951: 2924:(6321): 42–4. 2908: 2890: 2865: 2862:on 2008-07-14. 2847: 2833: 2815: 2791: 2761: 2731: 2705: 2687: 2607: 2586: 2559: 2520:(5): 687–696. 2500: 2482: 2435:Usoskin, I. G. 2426: 2407:(6): 397–401. 2388: 2369: 2323: 2275: 2230:(21): 211101. 2205: 2113: 2076:(1): 301–309. 2047: 2002: 1980: 1954: 1890: 1871: 1838: 1783: 1747:Houghton, J.T. 1735: 1713: 1678: 1676: 1673: 1671: 1670: 1665: 1663:Sun life cycle 1660: 1655: 1650: 1645: 1640: 1635: 1629: 1627: 1624: 1601: 1598: 1533:Main article: 1530: 1527: 1517:of objects in 1489: 1488: 1481: 1478: 1459: 1456: 1444:High Frequency 1429:communications 1408:) through the 1394:Main article: 1391: 1388: 1381: 1352: 1349: 1347: 1344: 1335: 1334: 1327: 1324: 1311: 1308: 1275: 1272: 1191: 1188: 1186:wind systems. 1157:solar constant 1121:Main article: 1118: 1115: 1113: 1110: 1084: 1081: 1027: 1024: 1022: 1019: 1007: 1004: 993: 990: 988: 985: 984: 983: 979: 975: 970: 966: 959: 953: 947:In studies of 945: 925: 922: 910:de Vries cycle 901: 898: 842: 839: 827:Main article: 824: 821: 807: 804: 791: 788: 731: 728: 704: 701: 665:magnetic field 613:Main article: 610: 607: 599:Main article: 596: 593: 586:Solar cycle 23 584:Main article: 581: 578: 568:Solar cycle 24 566:Main article: 563: 560: 545:Solar cycle 25 543:Main article: 540: 537: 535: 532: 522: 521: 518: 515: 513:Modern Maximum 509: 508: 505: 502: 500:Dalton Minimum 496: 495: 492: 489: 483: 482: 479: 476: 474:Spörer Minimum 470: 469: 466: 463: 459: 458: 455: 452: 448: 447: 444: 441: 437: 436: 433: 430: 424: 423: 420: 417: 397:Neoproterozoic 368: 365: 348:Horace Babcock 332: 331: 328: 325: 322:active regions 219: 212: 211: 204: 197: 196: 195: 194: 193: 188:Main article: 185: 182: 169: 166: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 8291: 8280: 8277: 8275: 8272: 8271: 8269: 8259: 8249: 8247: 8237: 8235: 8225: 8223: 8218: 8213: 8211: 8201: 8197: 8184: 8181: 8179: 8176: 8174: 8171: 8170: 8167: 8156: 8153: 8150: 8147: 8146: 8144: 8140: 8137: 8133: 8122: 8119: 8116: 8113: 8112: 8110: 8106: 8099: 8096: 8093: 8090: 8089: 8087: 8083: 8076: 8073: 8070: 8067: 8066: 8064: 8060: 8053: 8050: 8047: 8044: 8043: 8041: 8037: 8030: 8027: 8024: 8021: 8020: 8018: 8014: 8011: 8007: 7996: 7993: 7992: 7990: 7986: 7979: 7976: 7973: 7970: 7969: 7967: 7963: 7956: 7953: 7950: 7947: 7946: 7944: 7940: 7933: 7930: 7927: 7924: 7923: 7921: 7917: 7910: 7907: 7906: 7904: 7900: 7897: 7893: 7888: 7873: 7870: 7867: 7864: 7863: 7861: 7857: 7850: 7847: 7844: 7841: 7840: 7838: 7834: 7827: 7824: 7823: 7821: 7817: 7814: 7810: 7806: 7799: 7794: 7792: 7787: 7785: 7780: 7779: 7776: 7764: 7756: 7755: 7752: 7746: 7743: 7741: 7738: 7736: 7733: 7732: 7730: 7726: 7722: 7718: 7716: 7712: 7706: 7703: 7701: 7698: 7696: 7693: 7691: 7690:Space weather 7688: 7686: 7685:Space climate 7683: 7681: 7678: 7676: 7673: 7671: 7668: 7666: 7663: 7661: 7660:Solar physics 7658: 7656: 7653: 7651: 7648: 7646: 7643: 7641: 7638: 7636: 7633: 7631: 7628: 7626: 7623: 7621: 7618: 7612: 7609: 7608: 7607: 7604: 7603: 7602: 7599: 7597: 7594: 7590: 7589:Lunar eclipse 7587: 7585: 7582: 7581: 7580: 7577: 7576: 7574: 7570: 7564: 7561: 7559: 7556: 7554: 7551: 7549: 7546: 7544: 7543:Current sheet 7541: 7540: 7538: 7536: 7532: 7526: 7523: 7521: 7518: 7516: 7513: 7511: 7508: 7506: 7503: 7501: 7500:Solar minimum 7498: 7496: 7495:Solar maximum 7493: 7491: 7490:Active region 7488: 7484: 7481: 7480: 7479: 7476: 7475: 7473: 7471: 7467: 7457: 7454: 7452: 7449: 7447: 7444: 7442: 7439: 7437: 7434: 7432: 7429: 7427: 7424: 7422: 7419: 7417: 7414: 7413: 7411: 7409: 7405: 7399: 7396: 7394: 7391: 7389: 7386: 7385: 7383: 7381: 7377: 7371: 7370:Ellerman bomb 7368: 7366: 7363: 7361: 7358: 7356: 7353: 7351: 7348: 7347: 7345: 7343: 7339: 7336: 7334: 7330: 7324: 7321: 7319: 7316: 7314: 7311: 7309: 7306: 7305: 7303: 7301: 7297: 7291: 7288: 7287: 7284: 7280: 7273: 7268: 7266: 7261: 7259: 7254: 7253: 7250: 7244: 7241: 7237: 7236: 7231: 7229: 7226: 7224: 7221: 7219: 7218:SOHO Web Site 7216: 7214: 7211: 7209: 7208:NASA's Cosmos 7206: 7204: 7201: 7199: 7196: 7193: 7189: 7186: 7184: 7180: 7176: 7173: 7171: 7168: 7166: 7163: 7160: 7156: 7153: 7150: 7147:. ESA SP-463. 7146: 7140: 7136: 7132: 7128: 7124: 7119: 7116: 7112: 7111: 7107: 7101: 7095: 7091: 7090: 7084: 7080: 7079: 7073: 7069: 7065: 7061: 7057: 7053: 7049: 7044: 7039: 7035: 7031: 7026: 7022: 7018: 7014: 7010: 7006: 7002: 6997: 6993: 6989: 6985: 6981: 6977: 6973: 6969: 6965: 6960: 6956: 6952: 6948: 6944: 6940: 6936: 6931: 6926: 6922: 6918: 6913: 6909: 6905: 6900: 6895: 6891: 6887: 6883: 6879: 6874: 6869: 6865: 6861: 6857: 6852: 6851: 6847: 6839: 6835: 6831: 6827: 6823: 6819: 6814: 6809: 6805: 6801: 6800:Solar Physics 6794: 6791: 6786: 6782: 6777: 6772: 6767: 6762: 6758: 6754: 6750: 6743: 6740: 6735: 6731: 6727: 6723: 6719: 6715: 6710: 6705: 6701: 6697: 6696:Solar Physics 6690: 6687: 6682: 6678: 6674: 6670: 6666: 6662: 6657: 6652: 6648: 6644: 6643:Solar Physics 6637: 6634: 6628: 6623: 6619: 6615: 6611: 6607: 6600: 6593: 6590: 6585: 6581: 6576: 6571: 6567: 6563: 6558: 6553: 6549: 6545: 6541: 6534: 6531: 6525: 6520: 6515: 6510: 6506: 6502: 6498: 6491: 6488: 6482: 6477: 6473: 6469: 6464: 6459: 6455: 6451: 6447: 6440: 6437: 6431: 6426: 6422: 6418: 6413: 6408: 6404: 6400: 6396: 6389: 6386: 6380: 6375: 6370: 6365: 6361: 6357: 6353: 6346: 6343: 6332:on 2001-11-04 6331: 6327: 6323: 6316: 6313: 6310: 6299:on 2005-11-15 6298: 6294: 6293: 6288: 6282: 6279: 6267: 6266: 6261: 6255: 6252: 6247: 6243: 6239: 6235: 6231: 6227: 6220: 6217: 6211: 6206: 6202: 6198: 6194: 6190: 6186: 6179: 6176: 6172: 6166: 6162: 6161: 6156: 6149: 6146: 6142: 6141:New Scientist 6138: 6133: 6130: 6126: 6125:New Scientist 6123: 6118: 6115: 6110: 6106: 6101: 6096: 6092: 6088: 6084: 6080: 6076: 6069: 6066: 6061: 6057: 6052: 6047: 6043: 6039: 6035: 6031: 6027: 6020: 6017: 6013: 6007: 6004: 5999: 5995: 5991: 5987: 5983: 5979: 5975: 5971: 5964: 5961: 5955: 5954:10044/1/18859 5950: 5946: 5942: 5938: 5934: 5931:(11): 753–7. 5930: 5926: 5925: 5917: 5910: 5907: 5896:on 2011-08-04 5895: 5891: 5885: 5881: 5880: 5875: 5871: 5865: 5862: 5857: 5853: 5849: 5845: 5841: 5837: 5830: 5827: 5822: 5816: 5812: 5808: 5804: 5803:10.17226/4778 5800: 5796: 5792: 5785: 5782: 5777: 5773: 5769: 5765: 5761: 5757: 5750: 5747: 5742: 5738: 5731: 5728: 5723: 5719: 5715: 5711: 5707: 5703: 5698: 5693: 5689: 5685: 5678: 5675: 5669: 5664: 5660: 5656: 5652: 5648: 5644: 5637: 5634: 5629: 5625: 5620: 5615: 5611: 5607: 5603: 5599: 5595: 5588: 5585: 5579: 5574: 5570: 5566: 5563:(D14): 4211. 5562: 5558: 5554: 5547: 5544: 5538: 5533: 5529: 5525: 5521: 5517: 5513: 5506: 5503: 5492: 5488: 5483: 5478: 5474: 5470: 5466: 5462: 5461: 5453: 5449: 5443: 5440: 5434: 5429: 5425: 5421: 5417: 5413: 5409: 5402: 5399: 5388: 5384: 5380: 5376: 5372: 5368: 5363: 5358: 5354: 5350: 5343: 5336: 5333: 5328: 5324: 5319: 5314: 5310: 5306: 5302: 5298: 5294: 5290: 5286: 5282: 5278: 5271: 5268: 5256: 5252: 5246: 5243: 5232:on 2015-08-15 5231: 5227: 5215:on 2007-06-04 5211: 5207: 5201: 5197: 5193: 5188: 5183: 5179: 5175: 5171: 5167: 5160: 5153: 5150: 5145: 5141: 5134: 5131: 5126: 5122: 5118: 5114: 5110: 5106: 5099: 5096: 5091: 5087: 5083: 5079: 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3659: 3655: 3651: 3647: 3643: 3639: 3635: 3632:(1–2): 5–19. 3631: 3627: 3626: 3625:Solar Physics 3618: 3611: 3608: 3603: 3599: 3595: 3591: 3587: 3583: 3579: 3575: 3571: 3567: 3560: 3553: 3551: 3547: 3542: 3538: 3534: 3530: 3526: 3522: 3518: 3514: 3513: 3505: 3502: 3498: 3493: 3490: 3485: 3481: 3476: 3471: 3467: 3463: 3459: 3455: 3451: 3444: 3441: 3430: 3426: 3420: 3417: 3412: 3408: 3402: 3399: 3394: 3390: 3386: 3382: 3378: 3374: 3370: 3366: 3361: 3356: 3352: 3348: 3347:Solar Physics 3341: 3338: 3333: 3329: 3325: 3321: 3316: 3311: 3307: 3303: 3299: 3295: 3294:Solar Physics 3291: 3284: 3281: 3276: 3272: 3268: 3264: 3260: 3256: 3252: 3248: 3241: 3238: 3233: 3229: 3225: 3221: 3217: 3213: 3209: 3205: 3200: 3195: 3191: 3187: 3183: 3176: 3173: 3168: 3164: 3160: 3156: 3152: 3148: 3144: 3140: 3135: 3130: 3126: 3122: 3118: 3111: 3108: 3103: 3099: 3095: 3091: 3087: 3083: 3078: 3073: 3069: 3065: 3057: 3054: 3049: 3045: 3040: 3035: 3031: 3027: 3022: 3017: 3013: 3009: 3005: 2998: 2995: 2990: 2986: 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2282: 2280: 2276: 2271: 2267: 2263: 2259: 2255: 2251: 2247: 2243: 2238: 2233: 2229: 2225: 2224: 2219: 2215: 2209: 2206: 2195:on 2015-11-02 2194: 2190: 2186: 2173: 2169: 2165: 2161: 2157: 2153: 2149: 2145: 2141: 2137: 2130: 2126: 2120: 2118: 2114: 2109: 2105: 2101: 2097: 2093: 2089: 2084: 2079: 2075: 2071: 2064: 2060: 2054: 2052: 2048: 2043: 2039: 2035: 2031: 2026: 2021: 2017: 2013: 2006: 2003: 1998: 1994: 1990: 1984: 1981: 1977: 1973: 1967: 1965: 1963: 1961: 1959: 1955: 1950: 1946: 1942: 1938: 1934: 1930: 1926: 1922: 1918: 1914: 1910: 1906: 1905: 1900: 1899:Eddy, John A. 1894: 1891: 1886: 1883:(in German). 1882: 1875: 1872: 1867: 1860: 1857:(in German). 1856: 1852: 1845: 1843: 1839: 1834: 1830: 1826: 1822: 1818: 1814: 1809: 1804: 1800: 1796: 1795: 1794:Solar Physics 1787: 1784: 1781: 1777: 1774: 1762: 1758: 1757: 1752: 1748: 1742: 1740: 1736: 1732: 1728: 1722: 1720: 1718: 1714: 1710: 1709:public domain 1693: 1689: 1683: 1680: 1674: 1669: 1666: 1664: 1661: 1659: 1656: 1654: 1651: 1649: 1646: 1644: 1641: 1639: 1636: 1634: 1631: 1630: 1625: 1623: 1620: 1619: 1613: 1611: 1607: 1599: 1597: 1595: 1591: 1586: 1582: 1579:Although the 1577: 1573: 1569: 1567: 1562: 1558: 1554: 1550: 1546: 1542: 1536: 1528: 1526: 1524: 1520: 1516: 1515:orbital decay 1511: 1509: 1505: 1500: 1498: 1493: 1486: 1482: 1479: 1476: 1472: 1471: 1470: 1467: 1463: 1457: 1455: 1453: 1449: 1445: 1441: 1438: 1434: 1430: 1427: 1423: 1419: 1415: 1411: 1407: 1403: 1397: 1389: 1387: 1384: 1377: 1373: 1369: 1365: 1360: 1358: 1357:chronobiology 1350: 1345: 1343: 1341: 1332: 1328: 1325: 1322: 1317: 1316: 1315: 1309: 1307: 1304: 1302: 1297: 1293: 1289: 1284: 1282: 1273: 1271: 1269: 1265: 1261: 1255: 1253: 1249: 1244: 1240: 1235: 1233: 1229: 1225: 1221: 1217: 1209: 1205: 1201: 1196: 1189: 1187: 1185: 1181: 1180:stratospheric 1176: 1173: 1169: 1164: 1160: 1158: 1153: 1151: 1147: 1142: 1139: 1135: 1131: 1124: 1116: 1111: 1109: 1106: 1102: 1098: 1093: 1090: 1082: 1080: 1078: 1073: 1070: 1068: 1064: 1060: 1056: 1051: 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393:Early Permian 390: 389:Boreal period 386: 382: 373: 367:Cycle history 366: 364: 362: 358: 357:Babcock Model 354: 349: 345: 340: 338: 329: 326: 323: 319: 318: 317: 315: 310: 305: 303: 299: 295: 291: 287: 282: 280: 276: 272: 268: 267:Gustav Spörer 263: 261: 257: 253: 249: 245: 241: 237: 233: 222: 216: 207: 201: 191: 183: 181: 179: 178:solar minimum 175: 174:Solar maximum 167: 152: 150: 146: 141: 139: 134: 132: 128: 123: 121: 115: 113: 109: 105: 104:coronal loops 101: 97: 93: 89: 88:Sun's surface 85: 81: 77: 73: 72:Schwabe cycle 69: 68:sunspot cycle 65: 61: 52: 46: 41: 37: 33: 19: 8274:Solar cycles 8258:Solar System 8135:21st century 8009:20th century 7895:19th century 7812:18th century 7805:Solar cycles 7804: 7670:Solar System 7640:Solar energy 7635:Solar dynamo 7596:Heliophysics 7477: 7426:Coronal loop 7421:Coronal hole 7398:Moreton wave 7380:Chromosphere 7234: 7126: 7122: 7088: 7077: 7033: 7029: 7004: 7000: 6967: 6963: 6920: 6916: 6863: 6859: 6803: 6799: 6793: 6756: 6752: 6742: 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Retrieved 1691: 1682: 1616: 1614: 1603: 1585:brown dwarfs 1578: 1574: 1570: 1538: 1535:Solar dynamo 1529:Solar dynamo 1523:thermosphere 1512: 1502:The current 1501: 1497:Paraná River 1494: 1490: 1468: 1464: 1461: 1440:broadcasters 1399: 1361: 1354: 1336: 1313: 1305: 1285: 1277: 1256: 1254:satellites. 1236: 1224:chromosphere 1213: 1206:(Japan) and 1184:tropospheric 1165: 1161: 1154: 1150:Photospheric 1143: 1126: 1094: 1086: 1077:space debris 1074: 1071: 1067:Mars Mission 1062: 1052: 1029: 1016: 1009: 935: 909: 905: 903: 890: 874:beryllium-10 858:Sami Solanki 851: 846: 844: 832: 811: 809: 801: 784: 755:solar flares 749:produced by 743: 724: 709:Solar facula 685: 669: 646: 634: 604: 589: 571: 548: 529: 525: 385:beryllium-10 378: 341: 333: 306: 294:Spörer's law 283: 264: 229: 171: 143:The current 142: 135: 124: 119: 116: 100:solar flares 71: 67: 63: 59: 57: 36: 8246:Outer space 8234:Spaceflight 7728:Exploration 7606:Solar deity 7553:Heliosheath 7535:Heliosphere 7505:Wolf number 7478:Solar cycle 7342:Photosphere 6649:(6): 2333. 5735:Sloan, T.; 5653:(8): 4001. 5287:(1): 3707. 4874:(5): 1199. 4027:Radiocarbon 3014:: 1038949. 2828:www.sidc.be 2630:(1): 5209. 2445:(2): L154. 1418:propagation 1414:cosmic rays 1364:ozone layer 1346:Terrestrial 1216:photosphere 1130:radiometers 1112:Atmospheric 1089:cosmic rays 1040:solar cells 906:Suess cycle 900:Suess cycle 894:heliosphere 866:heliosphere 835:Wolf number 763:ultraviolet 736:Solar flare 713:Solar plage 661:magnetogram 554:(SWPC) and 260:Wolf number 256:Rudolf Wolf 221:Rudolf Wolf 60:solar cycle 8268:Categories 7680:Solar time 7601:In culture 7558:Heliopause 7510:Solar wind 7441:Prominence 7333:Atmosphere 7318:Tachocline 6873:1502.07020 6813:2304.14168 6709:1803.08692 6557:1609.07761 6507:(2). 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