The Sun is the nearest star to our earth, the only one high-resolution imaging observed and studied in the universe. It is the only source of light and heat indispensable for all life on the earth, maintaining a proper environment required for human existence and all life activities on the earth. Therefore, the study on solar activity and its varying pattern is very important for the research and service on the Sun-Earth relations, the research and prevention of some natural disasters. Firstly, the filament background knowledge and the research status of filament long-term activity patterns are introduced briefly. Then the statistical characteristic analysis of filament long-term activity is presented in detail. The main results are as follows: 1. In order to better understand the behavior of “rush to the poles”, we used the cross-correlation analysis and the wavelet transform methods to investigate the periodic characteristics and the phase relationship of two groups of solar filaments at high latitudes observed from March 1919 to December 1989. The length of the solar cycle derived from the continuous wavelet transform is a function of latitude, but still shows a significant 11-year cycle. The most significant periods of the solar filaments, respectively at higher latitudes than 50? and 60?, are 10.77 and 10.62 years by using the wavelet transform method. The solar filaments at higher latitudes than 50? have a time lead of six months with respect to the ones at higher latitudes than 60? from the cross-correlation analysis. Different solar cycles exhibited different phase relationship between two parts of solar filaments. The analysis of the cross-wavelet transform also indicates that the solar filaments at higher latitudes than 50? lead the ones at higher latitudes than 60? in the entire time interval. The relationship between the phase difference of two groups of solar filaments and the intensity of solar activity is also discussed. What’s more, the poleward shifting speeds are estimated. 2. Cross-correlation analysis and wavelet transform methods are used to investigate whether high-latitude solar activity leads low-latitude solar activity in time phase or not, using the data of the Carte Synoptique solar filaments archive from Carrington solar rotations (CRs) 876 to 1823. From the cross-correlation analysis, high-latitude solar filaments have a time lead of 12 CRs with respect to low-latitude ones. Both the cross-wavelet transform and wavelet coherence indicate that high-latitude solar filaments lead low-latitude ones in time phase. Furthermore, low-latitude solar activity is better correlated with high-latitude solar activity of the previous cycle than with that of the following cycle, which is statistically significant. Thus, the results confirm that high-latitude solar activity in the polar regions is indeed better correlated with low-latitude solar activity of the following cycle than with that of the previous cycle, namely, leading in time phase. 3. In the present study, we investigate the north-south asymmetry of solar filaments at low (< 50?) and high (>60?) latitudes, respectively, using daily filament numbers from January 1998 to November 2008 (solar cycle 23). We found that the northern hemisphere is dominant at low latitudes for cycle 23. However, a similar asymmetry does not occur for solar filaments at high latitudes. Thus, the hemispheric asymmetry of solar filaments at high latitudes in a cycle appears to have little connection with that at low latitudes. Our results support that the observed magnetic fields at high latitudes includes two components: one comes from the emergence of the magnetic fields from the solar interior and the other comes from the drift of the weak magnetic activity at low latitudes. 4. We present a case study of two successive filament eruptions at the southeast limb of the Sun observed by Solar Dynamics Observatory (SDO) on 2012 April 19. At the initial stage of the firs
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