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1.
对于太阳活动22年周期的成因机制长期存在着争论.本文借助于行星会合指数以及开普勒第三定律,对太阳绕太阳系质心运动周期进行了分析计算.结果发现,太阳绕太阳系质心运动存在22.1826年显著周期,这与太阳磁场变化的22.20年周期相吻合.并从太阳系角动量守恒的角度解释了两者之间的成因联系:在太阳绕太阳系质心运动的准22年周期中,太阳系质心与太阳质心逐步接近而后逐步分离.当两个质心之间的距离接近零的时候,太阳轨道角动量与自转角动量叠加,会导致太阳自转角速度的加快;当两个质心之间的距离逐渐远离的时候,则导致太阳自转角速度的减慢.这可能是引发太阳活动和太阳磁场变化的原因.这一新认识为太阳活动准22年周期成因机制的解释提供了新的线索和依据. 相似文献
2.
R. T. Gushchina A. V. Belov V. N. Obridko B. D. Shelting 《Geomagnetism and Aeronomy》2010,50(4):436-442
Based on observations of long-term variations in galactic cosmic rays (CRs) on Earth and in the near-Earth space, we have
determined, using our own semiempirical model, modulation of galactic CRs during solar cycles 19–23. The modulation model
relates CR variations to the characteristics of the solar magnetic field obtained for the surface of the solar wind source
at distances of 2.50 and 3.25 solar radii. The main focus is CR behavior at the minimums of cycles 19–23 and specific features
of CR modulation at a prolonged (as compared to previous cycles) minimum of cycle 23, which is still ongoing. CR modulation
at minimums related to a change in the solar field dipole component during this period of the cycle has been considered. It
is indicated that the long-term variations in CRs are better described if the last two years (2007 and 2008) of cycle 23 with
anomalously low solar activity (SA) are included in the model. The role and value of the contribution of the cyclic variations
in each index used in the proposed CR modulation model to the observed CR modulation have been estimated. 相似文献
3.
《Journal of Atmospheric and Solar》2000,62(13):1207-1213
It has previously been demonstrated that the mean land air temperature of the Northern hemisphere could adequately be associated with a long-term variation of solar activity as given by the length of the approximately 11-year solar cycle. Adding new temperature data for the 1990s and expected values for the next sunspot extrema we test whether the solar cycle length model is still adequate. We find that the residuals are now inconsistent with the pure solar model. We conclude that since around 1990 the type of Solar forcing that is described by the solar cycle length model no longer dominates the long-term variation of the Northern hemisphere land air temperature. 相似文献
4.
《Journal of Atmospheric and Solar》2000,62(5):335-346
The effect of the 11-year solar cycle on the response of the stratospheric geopotential height and temperature fields at 10 and 30 hPa in winter to solar activity oscillations with periods related to the period of the Sun’s rotation (27.2 days) is discussed, applying methods of statistical spectral analysis to daily data for the period from 1965 to 1996. Atmospheric responses for three periodicities — 27.2 days (period of the Sun’s rotation), 25.3 days (periodicity caused by the modulation of the 27.2 days oscillation by annual atmospheric variation), and 54.4 days (doubled period of the solar rotation) — are studied. A significant effect of the 11-year solar cycle on the atmospheric response to the 27.2 days solar periodicity has not been found. We explain it by a frequency shift of the response from the 27.2 days to the 25.3 days periodicity via amplitude modulation. For the 25.3 days oscillation, prominent differences between the maximum and minimum of the 11-year solar cycle have been found in the coherence between the 10.7 cm solar radio flux and the height/temperature fields: the relationships are stronger at solar maximum than at the minimum of the 11-year cycle. The same differences, but to a greater extent, are revealed for the oscillation with a period of 54.4 days. Coherence and amplitude estimates for this doubled solar rotation periodicity exhibit strong differences between extrema of the 11-year solar cycle. Phase estimates also demonstrate a clear difference between high and low solar activity: on the average, the delay of the atmospheric response after the solar signal is smaller at solar maximum than at solar minimum. Thus, we conclude that the mechanism of the influence of the 11-year solar cycle on the winter middle stratosphere can include both a direct effect of the frequency corresponding to the doubled solar rotation periodicity and an indirect effect of modulation of the intensity of the interaction between the solar 27.2 days oscillation and seasonal atmospheric variations. 相似文献
5.
作者发现：太阳辐射,地球自转与公转,黄、赤交角的存在,陆地和海洋在地球表面南、北半球的不规则、不对称地理分布,及地球内部因〖ZZ(〗核外液体〖ZZ)〗形成的分层结构,构成了一套天然的能使地球产生自由章动的日、地间动量（能量）相耦合的物理机制.经研究,由该机制产生的极移具有以下主要特征：（1）极移轨迹的运动周期为13个月（0.92周/年）,该周期由二个主要分量组成,一个为12个月（1周/年）,另一个是14.1个月（0.85周/年,即钱德勒周期）.（2）极移运动轨迹是是椭圆,短半轴（b）与长半轴(a)之比为0.86;扁率（a\|b/a）为1：7.1.（3）瞬时极移振幅|m|的变化：对1周/年项,|m|随太阳回归运动而变化,在二至点时最大,在二分点时最小,具有对称性;对0.85周/年项,|m|随太阳回归运动而变化,在夏至点最大,每年12月5日左右最小.（4）瞬时极移存在反向运动（由东向西）.在1周/年项极移运动中,自转极的正、反方向运动振幅的贡献各占50%;在0.85周/年项的极移运动中,反向运动的时间仅有33天,约占正向运动时间的1/10,正向运动振幅的贡献占96%,反向运动振幅的贡献大约占4%.（5）若以国际极点（CIO）为原点,自转极相对CIO的位移运动轨迹必然落在偏向于CIO的西侧.（6）极移振幅将长期保持下去而不会衰减,原因是太阳辐射为自转轴受迫摆动提供了长期、稳定的激发能源. 相似文献
6.
A Polish-made vertical ionosonde (VI) has been operated at the Kandilli Observatory in Istanbul, for almost one year (May 1993 - April 1994) as part of the COST 238, PRIME Project, The critical frequencies were obtained for every half-hour interval. The data obtained during this campaign, on the descending branch of solar cycle 22, and the data measured earlier in Istanbul for cycle 20 were analysed and the characteristic behaviour of the F2 region ionosphere over Istanbul has been determined. This is a unique data set for this area. Several markers of the solar cycle activities in terms of the daily relative sunspot numbers, F10.7 cm solar radio flux and solar flare index, and the magnetic daily index of Ap were then used to seek the possible influence of the solar and ionospheric activities on the critical frequencies observed in Istanbul. It was found that the solar flare index, as a solar activity index, was more reliable in determining quiet ionospheric days. It is shown that the minimum and maximum time values of the solar activity are more convenient for ionospheric prediction and modelling. 相似文献
7.
EISCAT radar experiments over a full solar cycle between January 1984 and March 1995 have been used to construct meridional neutral wind patterns in the ionospheric F region. For locally geomagnetically quiet periods the neutral winds have been binned according to season, solar activity, and universal time. The diurnal and seasonal behaviors and the effect of the solar flux are described. An empirical model of the meridional neutral wind for the high latitudes at eight altitudes in the ionospheric F region over a full solar cycle is presented. Results are compared with other recent empirical models. 相似文献
8.
Long-term variations in solar activity secular cycles have been studied using a method for the expansion of reconstructed sunspot number series Sn(t) for 11400 years in terms of natural orthogonal functions. It has been established that three expansion components describe more than 98% of all Sn(t) variations. In this case, the contribution of the first expansion component is about 92%. The averaged form of the 88year secular cycle has been determined based on the form of the first expansion coordinate function. The quasi-periodicities modulating the secular cycle have been revealed based on the time function conjugate to the first function. The quasi-periodicities modulating the secular cycle coincide with those observed in the Sn(t) series spectrum. A change in the secular cycle form and the time variations in this form are described by the second and third expansion components, the contributions of which are about 4 and 2%, respectively. The variations in the steepness of the secular cycle branches are more pronounced in the 200-year cycle, and the secular cycle amplitude varies more evidently in the 2300-year cycle. 相似文献
9.
The variability of foF2 in different phases of solar cycle 23 总被引：1，自引：0，他引：1
In this paper we examined the variations of the foF2 with solar activity for different local time and different seasons. Beside this we evaluated International Reference Ionosphere (IRI) models at different phases of solar cycle 23, different latitudes and different local time. We studied F2 layer critical frequency (foF2) of the ionosphere by using the flare index calculated by the Kandilli Observatory. For this purpose, we identified the months similar with high flare activity during the solar cycle 23. We chose 6 months which represented the different phases (ascending branch, maximum and descending branch) of the solar cycle. We also took into account the fact that these months were in different seasons. The hourly monthly means of observed foF2 data from four ionosonde stations for 6 months were calculated. On the other hand, the identical foF2 values of the same months were calculated for the year 1996, which is the minimum year of the previous solar activity cycle. We subtracted the foF2 values of 1996 from the values of the selected months of the last solar cycle to obtain the residuals, Δ(foF2). Then the magnitude of the residuals is compared through the cycle. We used IRI-2007 as well as IRI-2001 models to see the degree of deviation of the observed results from the predicted ones. We found that the predicted values of the ΔfoF2, which are calculated by the IRI-2007, fitted well with the observed Δ(foF2) and showed that the Δ(foF2) are dependent on the solar cycle variations in general. 相似文献
10.
《Journal of Atmospheric and Solar》2008,70(7):1025-1033
A tree-ring thickness time series from Passo Fundo (Southern Brazil) for the interval 1741–2004 was studied by spectral, wavelet and cross-wavelet analyses in order to identify the non-stationary characteristics in tree-ring and sunspot number data. Periods corresponding to the solar cycles of 11, 22, and 80 yr were found. The 11 yr solar cycle is detected in tree-ring data only during maximum solar activity interval from 1764 to 1804, 1824 to 1884, and 1924 to 1984. The Hale 22 yr solar cycle was observed in tree-ring wavelet map for the 1764–1864 and 1904–2004 intervals. The Gleissberg solar cycle was also observed in tree-ring wavelet map for the 1844–1904 interval. 相似文献
11.
A non-stationary transient oscillating process of the solar magnetic field polarity reversal of ≈3 years in duration has been established: a U-shaped dynamics in the wavelet representation of variations in the scintillation index of galactic cosmic rays (GCRs) (≈7, 13–14, and ≈7 solar rotations). The transient oscillating process of the field reversal is concluded with a sharp and deep decrease in the GCR intensity at the branch of 11-year cycle decline (1972, 1982, 1991, and 2003). The duration of the transient process inversely depends on the 11-year cycle amplitude. Retardation of relaxation oscillations during “weak” cycles (20 and 23) explains “anomalous” solar activity in 1972 and 2003. A decrease in the amplitude of the current cycle 23 is accompanied by an increase in its duration, which can mean that the 11-year cyclicity has become anomalous. The constancy of the energy released in a single cycle indicates that the 11-year cycle is the mechanism of energy regulation preventing the Sun from “overheating” at the critical temperature. 相似文献
12.
The hysteresis of foF2 is studied for several European stations over the whole 24-hour diurnal interval for the equinoctial months of the years just before and just after the solar cycle minimum for solar cycles 20 and 21. Based on previous results, the hysteresis is expected to develop best just for the equinoctial months and near the solar cycle minimum. The hysteresis is generally found to be negative, i.e. higher foF2 for the rising branch compared to the falling branch of solar cycle. However, this is not the case in some individual months of some years. The noontime hysteresis represents the hysteresis at other times of the day qualitatively (as to sign) but not quantitatively. The hysteresis appears to be relatively persistent from one solar cycle to another solar cycle in spring but not in autumn. A typical value for springtime hysteresis is about 0.5 MHz. The inclusion of hysteresis into long-term ionospheric and radio wave propagation predictions remains questionable. 相似文献
13.
M. G. Ogurtsov 《Geomagnetism and Aeronomy》2009,49(3):408-411
The average and maximal numbers of sunspot groups in the approaching solar cycle (cycle 24) have been predicted using paleoastrophysical information about solar activity during the last more than 10000 years. The linear and nonlinear prediction methods have been applied. It has been indicated that, from the standpoint of solar paleoastrophysics, the next cycle will most probably be average: the number of sunspot groups at a maximum will reach 68–101. The probability that cycle 24 will be powerful (more than 160 sunspot groups), which was predicted by some researchers, is low (not higher than 2%). 相似文献
14.
《Journal of Atmospheric and Solar》2003,65(4):469-482
Solar radiation (both total and in various wavelengths) varies at different time scales—from seconds to decades or centuries—as a consequence of solar activity. The energy received from the Sun is one of the natural driving forces of the Earth's atmosphere and since this energy is not constant, it has been argued that there must be some non-zero climate response to it. This response must be fully specified in order to improve our understanding of the climate system and the impact of anthropogenic activities on it. However, despite all the efforts, if and how subtle variations of solar radiation affect climate and weather still remains an unsolved puzzle. One key element that is very often taken as evidence of a response, is the similarity of periodicities between several solar activity indices and different meteorological parameters. The literature contains a long history of positive or negative correlations between weather and climate parameters like temperature, rainfall, droughts, etc. and solar activity cycles like the 27-day cycle, the prominent 11-year sunspot cycle, the 22-year Hale cycle and the Gleissberg cycle of 80–90 years. A review of these different cycles is provided as well as some of the correlative analyses between them and several stratospheric parameters (like stratospheric geopotential heights, temperature and ozone concentration) and tropospheric parameters (like temperature, rainfall, water level in lakes and river flooding, clouds) that point to a relationship of some kind. However, the suspicion on these relationships will remain as long as an indisputable physical mechanism, which might act to produce these correlations, is not available. 相似文献
15.
《Journal of Atmospheric and Solar》2008,70(15):1963-1970
An interpretation of the nature of the sudden ionospheric disturbance in terms of response to X-ray flux enhancement in the band 1–20 Å has been made by many authors. Last decades investigations revealed presence of important qualitative distinctions in spatially temporal pattern of geomagnetic response to solar flares featuring harder radiation spectra (with quanta energies above 100 keV). These distinctions can not be adequately described by classical theory implying ionization growing on E and D ionosperic layers and intensification of Sq-current system. In this respect, solar flare on 4 November 2003 characterizing by existence of two separate (time lag ~45 min) spectral maximums in X-rays range (average quantum energy <100 keV) and in γ-rays range (average quantum energy >100 keV), represents convenient proving ground for study of specifics the geomagnetic response to bursts marked by different hardness. In current article, we show that this flare has a number of unusual features including specific variation of accompanying current system and magnetospheric manifestation that is observed in trapped radiation fluxes and magnetic field on geosynchronous orbit. Possible physical mechanism leading to intensification of magnetospheric–ionospheric current system is discussed. 相似文献
16.
In this paper, we consider variations in energetic electron fluxes at a geostationary orbit, which are related to the Sun’s
rotation period, during two solar cycles. We use data on energetic electron fluxes obtained from the GOES (1986–2007) (>2
MeV) and LANL (1996–2007) (50–225 and 315–1500 keV) satellites. Within the solar cycle, we observed both periods of high flux
peak recurrence during several rotations and periods when there was no (or a low) 27-day recurrence. We show the similarity
and difference between manifestations of flux recurrences from cycle to cycle. Insignificant manifestation of recurrence and
its absence were observed mainly during the solar maximum. High electron flux recurrence was observed mainly at the phase
of decline in solar activity (near the solar minimum). We show that for both solar cycles, there were several days (within
the Bartels rotation) during which increased energetic electron fluxes would be most likely observed. 相似文献
17.
H.-L. Lam 《Journal of Atmospheric and Solar》2004,66(18):2162
A study has been carried out to determine the relationship between high energy relativistic (>2 MeV) electron fluence and auroral zone geomagnetic activity for a solar cycle. Data for 1987–1997, spanning Solar Cycle 22, were used in the study. The relativistic electron fluence data were based on fluxes observed by the GOES geosynchronous satellites. The geomagnetic data were the DRX indices derived from a Canadian magnetic observatory located in the auroral zone at Fort Churchill, near the footprint of field lines passing through geostationary satellites. This work, based on data from a solar cycle, confirms earlier findings using limited data from segments of a solar cycle of enhancement in fluence 2–3 days after increases in geomagnetic activity, and shows the cycle dependence of fluence with respect to geomagnetic activity. This study underlines the influence of recurrent coronal holes on fluence level as well as the possible role of Pc5 magnetic pulsations as an electron acceleration mechanism, and highlights the predictability of fluence from ground geomagnetic data. A fluence prediction algorithm can now solely be based on derived expressions relating fluence and DRX. Thus, a simple fluence prediction scheme can easily be implemented to provide a 2–3 day advance warning of space weather conditions hazardous to geosynchronous satellites, since during days of high fluence, the likelihood of internal charging in a satellite is high, with possible discharges that could result in satellite operational anomalies. For verification purpose, daily values of fluence for 1997–2000 and for January 1994 were postcast using the derived expressions. The postcast values were validated, and the results give credence to the fluence prediction scheme. 相似文献
18.
The relationships between a number of the main characteristic parameters of the cycle—amplitude, half-width, and growth phase duration—and the approximation parameters, which make it possible to estimate the average behavior of 11-year activity, have been derived based on the obtained analytical representations of the regularities in the solar activity variations during the cycle. Quasibiennial variations proceeding against a background of the cycle are distinctly associated with the solar magnetic field structure and the structure representation variations in the corona and in the flux of the solar neutrino radiation. This makes it possible to state that all these processes are parts of the common physical mechanism of solar variability. 相似文献
19.
《Journal of Atmospheric and Solar》2005,67(11):940-947
Three independent temperature datasets have been analyzed for quantifying the influence of the 11-year solar cycle modulation of the UV radiation. The datasets used include: US rocketsondes, the OHP lidar, and the global temperature database made by the successive SSU on the NOAA satellites, adjusted and provided by the UK Meteorological Office. These measurements cover the upper stratosphere and the mesosphere, where the direct photochemical effect is expected. The improvement of the analysis compared to previous ones was possible because the overall quality and the continuity of many data series have been checked more carefully during the last decade in order to look for anthropogenic fingerprints and the one used here have been recognized as the best series according to their temporal continuity. The analysis of the different data set is based on the same regression linear model. The 11-year solar temperature response observed presents a variable behavior, depending on the location. However, an overall adequate agreement among the results has been obtained, and thus the global picture of the solar impact in the upper stratosphere and lower mesosphere has been obtained and is presented here. In the tropics, a 1–2 K positive response in the mid and upper stratophere has been found, in agreement with photochemical theory and previous analyses. On the opposite, at mid-latitudes, negative responses of several Kelvin have been observed, during winters, in the analyses of the datasets analyzed here. In the mesosphere, at sub-tropic and mid-latitude regions, we observe a positive response all the year round increasing by a factor of two during winter. 相似文献
20.
地壳“轧展”效应对地震成因的解释 总被引：6，自引：0，他引：6
目前多数地球科学家认为,地球的演化（包括地壳运动和地震活动）是地球内部因素所决定的,地球外部因素是次要的,作认为,地球虽是庞大并具有确定边界的星体,从银河系看来,地球不能作为单独的星体存在,它必须依附太阳系才能生存下去,在太阳系的演化中,太阳是太阳系演化的核心和主导,太阳自身的演化控制着行星的演化是必然的。因此,研究太阳活动,太阳能量向地球的输送及太阳与地球间能量（包括动量和质量）相耦合的物理机 相似文献