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1.
The time series of total solar irradiance (TSI) satellite observations since 1978 provided by ACRIM and PMOD TSI composites are studied. We find empirical evidence for planetary-induced forcing and modulation of solar activity. Power spectra and direct data pattern analysis reveal a clear signature of the 1.09-year Earth-Jupiter conjunction cycle, in particular during solar cycle 23 maximum. This appears to suggest that the Jupiter side of the Sun is slightly brighter during solar maxima. The effect is observed when the Earth crosses the Sun-Jupiter conjunction line every 1.09 years. Multiple spectral peaks are observed in the TSI records that are coherent with known planetary harmonics such as the spring, orbital and synodic periods among Mercury, Venus, Earth and Jupiter: the Mercury-Venus spring-tidal cycle (0.20 year); the Mercury orbital cycle (0.24 year); the Venus-Jupiter spring-tidal cycle (0.32 year); the Venus-Mercury synodic cycle (0.40 year); the Venus-Jupiter synodic cycle (0.65 year); and the Venus-Earth spring tidal cycle (0.80 year). Strong evidence is also found for a 0.5-year TSI cycle that could be driven by the Earth’s crossing the solar equatorial plane twice a year and may indicate a latitudinal solar-luminosity asymmetry. Because both spring and synodic planetary cycles appear to be present and the amplitudes of their TSI signatures appear enhanced during sunspot cycle maxima, we conjecture that on annual and sub-annual scales both gravitational and electro-magnetic planet-sun interactions and internal non-linear feedbacks may be modulating solar activity. Gravitational tidal forces should mostly stress spring cycles while electro-magnetic forces could be linked to the solar wobbling dynamics, and would mostly stress the synodic cycles. The observed statistical coherence between the TSI records and the planetary harmonics is confirmed by three alternative tests. 相似文献
2.
The Chree superposition analysis of the luminosities of the planets Jupiter, Saturn, Uranus and Neptune indicates a correlation between solar activity and planetary luminosity. The variations of the solar constant in the visible range are considered to be too small to explain the observed changes in brightness. The interaction of solar extreme ultraviolet or solar wind particles with the atmospheres of these planets is probably responsible for the increased albedo during periods of high solar activity. 相似文献
3.
The wavelet analysis of the period of solar activity 总被引：1，自引：0，他引：1
Zhan La-sheng He Juan-mei Ye Yi-lin Zhao Hai-juan 《Chinese Astronomy and Astrophysics》2006,30(4):393-401
Using the wavelet technique, we analyzed the time series of solar radio fluxes at 2800 MHz as well as sunspot numbers and areas. The results are as follows: (1) These three data sets demonstrate that the most prominent period is 10.69 years and that all other periods are not obvious. (2) The wavelet power spectrum displays the changes of the power spectrum over the entire time-period range and shows the variations in the local power of a given period in a given time interval. Our analysis shows that periods shorter than one year are distinct only around solar activity maximum. (3) The time curves of the wavelet power at three periods (10.69 years, 5.11 years and 155.5 days) for the three times series are rather alike, with the same times of peaks and similar undulations. The shorter the period, the more frequent the fluctuations. 相似文献
4.
K. J. Li Q. X. Li P. X. Gao J. Mu H. D. Chen T. W. Su 《Journal of Astrophysics and Astronomy》2007,28(2-3):147-156
Long-term variation in the distribution of the solar filaments observed at the Observatorie de Paris, Section de Meudon from
March 1919 to December 1989 is presented to compare with sunspot cycle and to study the periodicity in the filament activity,
namely the periods of the coronal activity with the Morlet wavelet used. It is inferred that the activity cycle of solar filaments
should have the same cycle length as sunspot cycle, but the cycle behavior of solar filaments is globally similar in profile
with, but different in detail from, that of sunspot cycles. The amplitude of solar magnetic activity should not keep in phase
with the complexity of solar magnetic activity. The possible periods in the filament activity are about 10.44 and 19.20 years.
The wavelet local power spectrum of the period 10.44 years is statistically significant during the whole consideration time.
The wavelet local power spectrum of the period 19.20 years is under the 95% confidence spectrum during the whole consideration
time, but over the mean red-noise spectrum of α = 0.72 before approximate Carrington rotation number 1500, and after that the filament activity does not statistically show
the period. Wavelet reconstruction indicates that the early data of the filament archive (in and before cycle 16) are more
noiseful than the later (in and after cycle 17). 相似文献
5.
This work investigates the solar quasi-periodic cycles with multi-timescales and the possible relationships with planetary motions. The solar cycles are derived from long-term observations of the relative sunspot number and microwave emission at frequency of 2.80 GHz. A series of solar quasi-periodic cycles with multi-timescales are registered. These cycles can be classified into three classes: (1) the strong PLC (PLC is defined as the solar cycle with a period very close to the ones of some planetary motions, named as planetary-like cycle) which is related strongly with planetary motions, including nine periodic modes with relatively short period (P<12 yr), and related to the motions of the inner planets and of Jupiter; (2) the weak PLC, which is related weakly to planetary motions, including two periodic modes with relatively long period (P>12 yr), and possibly related to the motions of outer planets; (3) the non-PLC, for which so far there has been found no clear evidence to show the relationship with any planetary motions. Among the planets, Jupiter plays a key role in most periodic modes due to its sidereal motion or spring tidal motions associated with other planets. Among planetary motions, the spring tidal motion of the inner planets and of Jupiter dominates the formation of most PLCs. The relationships between multi-timescale solar periodic modes and the planetary motions will help us to understand the essential nature and prediction of solar activities. 相似文献
6.
Paleo-cosmic-ray (PCR) records based on cosmogenic 10Be and 14C data are used to study the variations in cosmic-ray intensity and solar activity over the past 9400 years. There are four strong correlations with the motion of the Jovian planets; the probability of occurring by chance being <?10?5. They are i) the PCR periodicities at 87, 350, 510, and 710 years, which closely approximate integer multiples of half the Uranus–Neptune synodic period; ii) eight periodicities in the torques calculated to be exerted by the planets on an asymmetric tachocline that approximate the periods observed in the PCR; iii) the maxima of the long-term PCR variations are coincident with syzygy (alignment) of the four Jovian planets in 5272 and 644 BP; and iv) in the time domain, the PCR intensity decreases during the first 60 years of the ≈?172 year Jose cycle (Jose, Astron. J. 70, 193, 1965) and increases in the remaining ≈?112 years in association with barycentric anomalies in the distance between the Sun and the center of mass of the solar system. Furthermore, sunspot and neutron-monitor data show that three anomalous sunspot cycles (4th, 7th, and 20th) and the long sunspot minimum of 2006 – 2009 CE coincided with the first and second barycentric anomalies of the 58th and 59th Jose cycles. Phase lags between the planetary and heliospheric effects are ≤?five years. The 20 largest Grand Minima during the past 9400 years coincided with the latter half of the Jose cycle in which they occurred. These correlations are not of terrestrial origin, nor are they due to the planets’ contributing directly to the cosmic-ray modulation process in the heliosphere. Low cosmic-ray intensity (higher solar activity) occurred when Uranus and Neptune were in superior conjunction (mutual cancellation), while high intensities occurred when Uranus–Neptune were in inferior conjunction (additive effects). Many of the prominent peaks in the PCR Fourier spectrum can be explained in terms of the Jose cycle, and the occurrence of barycentric anomalies. 相似文献
7.
Observational time series of the total sunspot area A in the visible solar hemisphere are analyzed. A technique that allows the instability of the scale of these series to be found and corrected has been developed. An internally homogeneous series of the index A on the Greenwich scale can be obtained from 1875 to the present. A method for the approximate calculation of the yearly mean A from the Wolf sunspot numbers known since 1700 is suggested to extend this series into the past. The resulting series of the index A characterizes the solar activity variations over a period of ～300 years. These data are used to study processes in the Solar System related to the variability of the central star. 相似文献
8.
The modulation model of the solar magnetic cycle for the time interval from 1650 to 1996 A.D. describes an harmonic oscillator with a basic (22.13 ± 0.05)-yr period, which is subjected to amplitude and phase variations that can be represented by a sum of trigonometric series. The simulated sunspot data explain 97.9% of cycle peak height variance and the residual standard deviation is 8.6 mean annual sunspots. A peak height of 139 for cycle 23 occurring in 2001 is predicted, whereas cycle 24 would have a maximum around 132 in 2014. Simulation of the sunspot numbers from 1000 until 2400 A.D. shows that the model recreates recurring minima (Maunder and Spörer Minimum). The prediction also expects a high level of amplitude modulation in the interval 1950–2010 with a rapid decrease afterwards. A greatly reduced cycle activity is reproduced by the simulation from about 2065 to 2100 A.D. No direct explanation of the long-term periodicities of the model can be advanced. The high-frequency contribution of the phase modulation, which accounts for the skewness of the solar cycle, shows coincidences with the orbital periods of Jupiter and Saturn, but no physical basis for the matching periodicities can be conceived. 相似文献
9.
A reconstruction of sunspot numbers for the last 1000 years was obtained using a sum of sine waves derived from spectral analysis of the time series of sunspot number R
z for the period 1700–1999. The time series was decomposed in frequency levels using the wavelet transform, and an iterative regression model (ARIST) was used to identify the amplitude and phase of the main periodicities. The 1000-year reconstructed sunspot number reproduces well the great maximums and minimums in solar activity, identified in cosmonuclides variation records, and, specifically, the epochs of the Oort, Wolf, Spörer, Maunder, and Dalton Minimums as well the Medieval and Modern Maximums. The average sunspot number activity in each anomalous period was used in linear equations to obtain estimates of the solar radio flux F
10.7, solar wind velocity, and the southward component of the interplanetary magnetic field. 相似文献
10.
The hypersonic analog for the interaction of the solar wind with Jupiter, Saturn, Uranus, Neptune and Pluto is used to provide estimates of shock shapes and locations as well as average magnetosheath and/or ionosheath properties for these planets. Several representative spacecraft flyby trajectories (designed for outer-planet Grand Tour simulations) are superimposed upon a series of figures in order to provide estimates of potential plasma and field parameters which may be encountered. Consideration is given first to the possibility that several of these planets have intrinsic magnetic fields and, secondly, to the interaction of the solar wind directly on the ionosphere should there actually be no intrinsic field. Saturn and Pluto are chosen as examples of this latter case. 相似文献
11.
U. M. Leiko 《Kinematics and Physics of Celestial Bodies》2016,32(6):299-306
The results of an analysis of the north–south asymmetry in solar activity and solar magnetic fields are reported. The analysis is based on solar mean magnetic field and solar polar magnetic field time series, 1975–2015 (http://wso.stanford.edu), and the Greenwich sunspot data, 1875–2015 (http://solarscience.msfc.nasa.gov/greenwch.shtml). A long-term cycle (small-scale magnetic fields, toroidal component) of ~140 years is identified in the north–south asymmetry in solar activity by analyzing the cumulative sum of the time series for the north–south asymmetry in the area of sunspots. A comparative analysis of the variations in the cumulative sums of the time series composed of the daily values of the sun’s global magnetic field and in the asymmetry of the daily sunspot data over the time interval 1975–2015 shows that the photospheric large-scale magnetic fields may also have a similar long-term cycle. The variations in the asymmetry of large-scale and small-scale solar magnetic fields (sunspot area) are in sync until 2005.5 and in antiphase since then. 相似文献
12.
太阳总辐照是指在地球大气层顶接收到的太阳总辐射照度,也叫"太阳常数",但它实际上并非常数。太阳总辐照随波长的分布即为太阳分光辐照。太阳辐照变化的研究,对理解太阳表面及内部活动的物理过程、机制,研究地球大气、日地关系,解决人类面临的全球气候变暖的挑战等,都具有重要意义。首先简单介绍了太阳辐照,回顾了太阳辐照的空间观测;接着介绍了观测数据的并合,以及对合成数据的一些研究;然后讨论了太阳辐照变化的原因,简述了太阳总辐照的重构及其在气候研究上的一些应用,并进行必要的评论;最后对未来的研究方向提出了一些看法。 相似文献
13.
Our study deals with the correlations between the solar activity on the one hand and the solar irradiance above the Earth’s
atmosphere and at ground level on the other. We analyzed the combined ACRIM I+II time series of the total solar irradiance
(TSI), the Mauna Loa time series of terrestrial insolation data, and data of terrestrial cosmic ray fluxes. We find that the
correlation between the TSI and the sunspot number is strongly non-linear. We interpret this as the net balance between brightening
by faculae and darkening by sunspots where faculae dominate at low activity and sunspots dominate at high activity. Such a
behavior is hitherto known from stellar analogs of the Sun in a statistical manner. We perform the same analysis for the Mauna
Loa data of terrestrial insolation. Here we find that the linear relation between sunspot number and insolation shows more
than 1% rise in insolation by sunspot number variations which is much stronger than for the TSI. Our conclusion is that the
Earth atmosphere acts as an amplifier between space and ground, and that the amplification is probably controlled by solar
activity. We suspect the cosmic rays intensity as the link between solar activity and atmospheric transparency. A Fourier
analysis of the time series of insolation shows three dominant peaks: 10.5, 20.4, and 14.0 years. As a matter of fact, the
cosmic rays data show the same pattern of significant peaks: 10.7, 22.4, and 14.9 years. This analogy supports our idea that
the cosmic rays variation has influence on the transparency of the Earth atmosphere. 相似文献
14.
Stephen R. Kane 《Icarus》2011,214(1):327-333
With more than 15 years since the first radial velocity discovery of a planet orbiting a Sun-like star, the time baseline for radial velocity surveys is now extending out beyond the orbit of Jupiter analogs. The sensitivity to exoplanet orbital periods beyond that of Saturn orbital radii however is still beyond our reach such that very few clues regarding the prevalence of ice giants orbiting solar analogs are available to us. Here we simulate the radial velocity, transit, and photometric phase amplitude signatures of the Solar System giant planets, in particular Uranus and Neptune, and assess their detectability. We scale these results for application to monitoring low-mass stars and compare the relative detection prospects with other potential methods, such as astrometry and imaging. These results quantitatively show how many of the existing techniques are suitable for the detection of ice giants beyond the snow line for late-type stars and the challenges that lie ahead for the detection true Uranus/Neptune analogs around solar-type stars. 相似文献
15.
Influence of the solar activity on the Indian Monsoon rainfall 总被引：1，自引：0，他引：1
We use 130 years data for studying correlative effects due to solar cycle and activity phenomena on the occurrence of the Indian Monsoon rainfall. We compute the correlation coefficients and significance of correlation coefficients for the seasonal and the annual data. We find that: (i) for the whole years 1871–2000, the spring and southwest monsoon rainfall variabilities have significant positive correlations with the sunspot activity during the corresponding period, (ii) the FFT and the wavelet analyses of the southwest monsoon rainfall variability show the periods 2.7, 16 and 22 year, respectively (similar to the periods found in sunspot occurrence data) and, (iii) there is a long-term trend indicating a gradual decrease of occurrence of rainfall variability by nearly 2.3 ± 1.3 mm/year and increase of sunspot activity by nearly 3.9 ± 1.5 sunspots/year compared to the activity of previous solar cycle.
We speculate in this study a possible physical connection between the occurrence of the rainfall variability and the sunspot activity, and the flux of galactic cosmic rays. Owing to long-term positive and significant correlation of the spring and southwest monsoon rainfall variabilities with the sunspot activity, it is suggested that solar activity may be included as one of the crucial parameter in modeling and predicting the Indian monsoon rainfall. 相似文献
16.
Three-dimensional numerical simulations show that large-scale latent heating resulting from condensation of water vapor can produce multiple zonal jets similar to those on the gas giants (Jupiter and Saturn) and ice giants (Uranus and Neptune). For plausible water abundances (3-5 times solar on Jupiter/Saturn and 30 times solar on Uranus/Neptune), our simulations produce ∼20 zonal jets for Jupiter and Saturn and 3 zonal jets on Uranus and Neptune, similar to the number of jets observed on these planets. Moreover, these Jupiter/Saturn cases produce equatorial superrotation whereas the Uranus/Neptune cases produce equatorial subrotation, consistent with the observed equatorial-jet direction on these planets. Sensitivity tests show that water abundance, planetary rotation rate, and planetary radius are all controlling factors, with water playing the most important role; modest water abundances, large planetary radii, and fast rotation rates favor equatorial superrotation, whereas large water abundances favor equatorial subrotation regardless of the planetary radius and rotation rate. Given the larger radii, faster rotation rates, and probable lower water abundances of Jupiter and Saturn relative to Uranus and Neptune, our simulations therefore provide a possible mechanism for the existence of equatorial superrotation on Jupiter and Saturn and the lack of superrotation on Uranus and Neptune. Nevertheless, Saturn poses a possible difficulty, as our simulations were unable to explain the unusually high speed (∼) of that planet’s superrotating jet. The zonal jets in our simulations exhibit modest violations of the barotropic and Charney-Stern stability criteria. Overall, our simulations, while idealized, support the idea that latent heating plays an important role in generating the jets on the giant planets. 相似文献
17.
We investigate the periodicity in the PMOD composite of the daily total solar irradiance (TSI) from 21 September 1978 to 9 June
2009. Besides the Schwabe cycle period (10.32 years), the quasi-rotation period is found to be statistically significant in
TSI, whose value is about 32 days, longer than that in sunspot activity (27 days), and it intermittently appears around the
sunspot maximum times. The quasi-rotation period in TSI is inferred to be mainly caused by sunspot activity, but to be modulated
by bright features as well. It was previously found that variations of TSI over a Schwabe solar cycle mainly come from the
combination of the sunspots’ blocking and the intensification due to bright faculae, plages, and network elements, with a
slight dominance of the bright-feature effect during the maximum of the Schwabe cycle. For the sunspot-blocking and the bright-feature
effect to contribute to TSI over a Schwabe solar cycle, the former is inferred to lead the latter by 29 days at least. 相似文献
18.
A method due to Schuster is used to test the hypothesis that solar activity is influenced by tides raised in the Sun's atmosphere by planets. We calculate the distribution in longtitude of over 1000 flares occurring in a 61/2 yr segment of solar cycle 19, referring the longitude system in turn to the orbital positions of Jupiter and Venus. The resulting distributions show no evidence for a tidal effect. 相似文献
19.
Periodic Appearance of Coronal Holes and the Related Variation of Solar Wind Parameters 总被引：1，自引：0，他引：1
We compared the variability of coronal hole (CH) areas (determined from daily GOES/SXI images) with solar wind (daily ACE
data) and geomagnetic parameters for the time span 25 January 2005 until 11 September 2005 (late declining phase of solar
cycle 23). Applying wavelet spectral analysis, a clear 9-day period is found in the CH time series. The GOES/SXI image sequence
suggests that this periodic variation is caused by a mutual triangular distribution of CHs ∼120° apart in longitude. From
solar wind parameters a 9-day periodicity was obtained as well, simultaneously with the 9-day period in the CH area time series.
These findings provide strong evidence that the 9-day period in solar wind parameters, showing up as higher harmonic of the
solar rotation frequency, is caused by the “periodic” longitudinal distribution of CHs on the Sun recurring for several solar
rotations. The shape of the wavelet spectrum from the Dst index matches only weakly with that from the CH areas and is more similar to the wavelet spectrum of the solar wind magnetic
field magnitude. The distinct 9-day period does not show up in sunspot group areas which gives further evidence that the solar
wind modulation is strongly related to CH areas but not to active region complexes. The wavelet power spectra for the whole
ACE data range (∼1998 – 2006) suggest that the 9-day period is not a singular phenomenon occurring only during a specific
time range close to solar minimum but is occasionally also present during the maximum and decay phase of solar cycle 23. The
main periods correspond to the solar rotation (27d) as well as to the second (13.5d) and third (9d) harmonic.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
20.
P. Zarka W.M. Farrell M.L. Kaiser E. Blanc W.S. Kurth 《Planetary and Space Science》2004,52(15):1435-1447
Radio signatures of lightning discharges have been detected by the Voyager spacecraft near Saturn and Uranus up to 40 MHz. Corresponding flux densities at the distance of the Earth are up to 1000 Jansky (Jy) for Saturn (1 event per minute above 50 Jy, with 30–300 ms duration) and up to a few tens of Jansky for Uranus. Low Frequency ARray LOFAR will allow us to detect and monitor the lightning activity at these two planets. Imaging will allow us to locate lightning sources on Saturn's disk (even if with moderate accuracy), which could then be correlated to optical imaging of clouds. Such observations could provide new information on electrification processes, atmospheric dynamics, composition, and geographical and seasonal variations, compared to the Earth. In addition, lightning may play a role in the atmospheric chemistry, through the production of non-equilibrium trace organic constituents potentially important for biological processes. LOFAR observations can also help us to assess the existence of lightning at Neptune (marginally detected by Voyager), at Venus (where their existence is very controversial), and at Mars (possibly resulting from dust cloud charging). At Jupiter, low-altitude ionospheric layers of meteoritic origin and/or intrinsically long discharge duration seem to prevent the emission and escape of high-frequency radio waves associated with lightning. LOFAR thus presents good possibilities for the detection and study of solar system planetary lightning; we also discuss its relevance to bring new information on Terrestrial lightning-related upper atmosphere transient phenomena (sprites, TIPPs…). Instrumental constraints are outlined. 相似文献