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The Decay Process of an α-configuration Sunspot
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作者 Yang Peng Zhi-Ke Xue +8 位作者 Xiao-Li Yan Aimee ANorton Zhong-Quan Qu Jin-Cheng Wang Zhe Xu Li-Heng Yang Qiao-Ling Li Li-Ping Yang Xia Sun 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第2期73-81,共9页
The decay of sunspot plays a key role in magnetic flux transportation in solar active regions(ARs).To better understand the physical mechanism of the entire decay process of a sunspot,an α-configuration sunspot in AR... The decay of sunspot plays a key role in magnetic flux transportation in solar active regions(ARs).To better understand the physical mechanism of the entire decay process of a sunspot,an α-configuration sunspot in AR NOAA 12411 was studied.Based on the continuum intensity images and vector magnetic field data with stray light correction from Solar Dynamics Observatory/Helioseismic and Magnetic Imager,the area,vector magnetic field and magnetic flux in the umbra and penumbra are calculated with time,respectively.Our main results are as follows:(1) The decay curves of the sunspot area in its umbra,penumbra,and whole sunspot take the appearance of Gaussian profiles.The area decay rates of the umbra,penumbra and whole sunspot are-1.56 MSH day^(-1),-12.61 MSH day^(-1) and-14.04 MSH day^(-1),respectively;(2) With the decay of the sunspot,the total magnetic field strength and the vertical component of the penumbra increase,and the magnetic field of the penumbra becomes more vertical.Meanwhile,the total magnetic field strength and vertical magnetic field strength for the umbra decrease,and the inclination angle changes slightly with an average value of about 20°;(3) The magnetic flux decay curves of the sunspot in its umbra,penumbra,and whole sunspot exhibit quadratic patterns,their magnetic flux decay rates of the umbra,penumbra and whole sunspot are-9.84 × 10^(19)Mx day^(-1),-1.59 × 10^(20)Mx day^(-1) and -2.60 × 10^(20)Mx day^(-1),respectively.The observation suggests that the penumbra may be transformed into the umbra,resulting in the increase of the average vertical magnetic field strength and the reduction of the inclination angle in the penumbra during the decay of the sunspot. 展开更多
关键词 SUN atmosphere-Sun magnetic fields-(Sun:)sunspots
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Signature of the 27-day variation in hemispheric sunspot activity and asymmetry during 2010-2015
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作者 Prithvi Raj Singh Ahmad Islam Saad Farid +1 位作者 Tarun Kumar Pant Abhay Kumar Singh 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第4期331-340,共10页
In the present work,we study the time evolution,significance of the N-S asymmetry excesses presented as a function of the solar cycle and prominent rotational periods(~27 d)separately for the northern and southern hem... In the present work,we study the time evolution,significance of the N-S asymmetry excesses presented as a function of the solar cycle and prominent rotational periods(~27 d)separately for the northern and southern hemispheres.We have investigated short-term variations of the hemispheric solar activity(sunspot numbers and sunspot areas)during the time period 2010-2015,which covers the ascending and the maximum phase of solar cycle 24.We have implemented the Lomb-Scargle periodogram and continuous wavelet transform power spectrum techniques to study the time evolution and dominant rotational periods separately for the northern and southern hemispheres,and whole solar disk.Our results showed that the northern hemisphere exhibited longer solar synodic periods than the southern hemisphere,indicating that the northern hemisphere has a lower rotation rate.Moreover,the northern hemisphere was found to be dominant before transferring to the southern hemisphere during mid-2013.Also,the sunspot areas clearly demonstrated a two-peak structure of solar activity in the northern and southern hemispheres respectively during 2012 and 2014.The statistical significance of the southern hemisphere affirmed enhanced excess during the maximum phase of solar cycle 24. 展开更多
关键词 sunspotS sunspot Area Asymmetry Solar Cycle
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The Sunspots
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作者 Angel Fierros Palacios 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第2期72-87,共16页
In the present paper, the theoretical frame work of magneto hydrodynamics (MHD) is used to give a solution of the problem about the origin, persistence and disappearance of the Sunspots;as well as their tendency to ap... In the present paper, the theoretical frame work of magneto hydrodynamics (MHD) is used to give a solution of the problem about the origin, persistence and disappearance of the Sunspots;as well as their tendency to appear as bipolar magnetic couples. According to the results obtained, a possible explanation about the change of polarity in both solar hemispheres is given. Heuristic but logical arguments about the periodicity of the phenomenon of the observed magnetic polarity and the tendency of couples of Sunspots to appear solely in certain latitudes that can be called tropical regions of the Sun are presented. Finally, an indirect experimental test is proposed to show the possible process that produces the polarity of the Sunspots in a given cycle, as well as the invertion of that polarity in the next solar cycle. 展开更多
关键词 MAGNETIC Field of the SPOTS sunspots’ Theory MAGNETIC Regulation of Thermal CONVECTION Polarity of the sunspotS Couples Solar CYCLE Structure and Stability of the SPOTS Life Time of the SPOTS
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基于SunSPOT无线传感器网络的水轮机组机械振动监测系统的研究 被引量:1
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作者 谢兴旺 刘好 《江汉大学学报(自然科学版)》 2013年第6期56-59,共4页
利用SunSPOT无线传感器网络硬软件平台开发了一套水轮机组机械振动监测系统。该系统能够对水轮机组转动部件的振动信息进行实时的采集、传输和存储。水电厂的控制中心对这些数据进行分析、处理并且作出判断决策,以确保水轮机组安全运行... 利用SunSPOT无线传感器网络硬软件平台开发了一套水轮机组机械振动监测系统。该系统能够对水轮机组转动部件的振动信息进行实时的采集、传输和存储。水电厂的控制中心对这些数据进行分析、处理并且作出判断决策,以确保水轮机组安全运行和适时检修,降低事故的发生概率。讨论了SunSPOT无线传感器网络硬件结构,6LoWPAN无线通信协议,基于Java语言的NetBeans软件开发平台以及SPOT WORLD虚拟机。介绍了终端节点的数据采集和传输,基站的数据接收和储存所用到的接口和类的代码。 展开更多
关键词 sunspot 无线传感器网络 机械振动 水轮机
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The Sunspot Cycle Leads to Origin and Epidemic Mechanism of Novel Coronavirus COVID-19 被引量:2
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作者 Jiang Wu 《Natural Science》 2020年第10期670-680,共11页
Listed examples of virus transmission epidemics that can be strongly transmitted through the air<span "=""> </span><span style="font-family:Verdana;">caused by sunspot change... Listed examples of virus transmission epidemics that can be strongly transmitted through the air<span "=""> </span><span style="font-family:Verdana;">caused by sunspot change cycle</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">analyzed the mechanism that promotes the generation of new viruses. From the schematic diagram of the changes in the combined force of the hydrodynamic effect of the sun sweeping the earth and the sweeping force, </span><span style="font-family:Verdana;">we </span><span style="font-family:Verdana;">obtain the </span><span style="font-family:Verdana;">places that are prone to light vortices are 30 degrees north latitude and 30 degrees</span><span "=""> </span><span style="font-family:Verdana;">south latitude on the east coast of the mainland creatively</span><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">The curved continental lines are perfect, the range of the light vortex generated is more obviously, and the effect is stronger. And the curved continental lines are perfect, the range of the light vortex generated is more obviously, and the effect is stronger. It is inferred that the light vortex produces the special amplified energy so</span><span style="font-family:Verdana;"> that can</span><span style="font-family:Verdana;"> make the virus mutate to produce a new highly infectious novel coronavirus. The earliest known place and time of the novel coronavirus origin are consistent with the reasoning of the new theory. Because the radius and frequency of the light vortex are different, the resulting virus strains are also different. Moreover, the fatality rate in the light vortex area is much higher than that in the non-light vortex area, indicating that the virus</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">s toxicity and lethality are higher in the light vortex area, so it can explain why Russia, India, and countries in the African equatorial region mortality are much lower than the United States, Italy, Spain and Brazil. Finally, preventive and recommended measures are proposed.</span> 展开更多
关键词 sunspot Cycle Virus Mutation Light Vortex Origin of Novel Coronavirus Epidemic Distribution 2019-nCoV
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Propagating slow sausage waves in a sunspot observed by the New Vacuum Solar Telescope 被引量:1
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作者 Song Feng Zheng Deng +2 位作者 Ding Yuan Zhi Xu Xiao Yang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第8期157-162,共6页
A sunspot is an ideal waveguide for a variety of magnetohydrodynamic waves,which carry a significant amount of energy to the upper atmosphere and could be used as a tool to probe the magnetic and thermal structure of ... A sunspot is an ideal waveguide for a variety of magnetohydrodynamic waves,which carry a significant amount of energy to the upper atmosphere and could be used as a tool to probe the magnetic and thermal structure of a sunspot.In this study,we used the New Vacuum Solar Telescope and took highresolution image sequences simultaneously in both Ti O(7058±10?A)and Hα(6562±2.5?A)bandpasses.We extracted the area and total emission intensity variations of sunspot umbra and analyzed the signals with synchrosqueezing transform.We found that the area and emission intensity varied with both three and five minute periodicity.Moreover,the area and intensity oscillated in phase with each other,this fact hold in both Ti O and Hαdata.We interpret this oscillatory signal as a propagating slow sausage wave.The propagation speed is estimated at about 8 km s^-1.We infer that this sunspot's umbra could have temperature as low as 2800–3500 K. 展开更多
关键词 Sun:sunspot Sun:oscillations magnetohydrodynamics(MHD) methods:data analysis
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Predicting the 25th solar cycle using deep learning methods based on sunspot area data 被引量:1
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作者 Qiang Li Miao Wan +2 位作者 Shu-Guang Zeng Sheng Zheng Lin-Hua Deng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第7期290-298,共9页
It is a significant task to predict the solar activity for space weather and solar physics. All kinds of approaches have been used to forecast solar activities, and they have been applied to many areas such as the sol... It is a significant task to predict the solar activity for space weather and solar physics. All kinds of approaches have been used to forecast solar activities, and they have been applied to many areas such as the solar dynamo of simulation and space mission planning. In this paper, we employ the long-shortterm memory(LSTM) and neural network autoregression(NNAR) deep learning methods to predict the upcoming 25 th solar cycle using the sunspot area(SSA) data during the period of May 1874 to December2020. Our results show that the 25 th solar cycle will be 55% stronger than Solar Cycle 24 with a maximum sunspot area of 3115±401 and the cycle reaching its peak in October 2022 by using the LSTM method. It also shows that deep learning algorithms perform better than the other commonly used methods and have high application value. 展开更多
关键词 Sun:activity Sun:solar cycle prediction Sun:sunspot area Method:deep neural network
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The Formation and Evolution of the Sun and the Source of Star Energy as Well as the Sunspots and Flares of the Sun 被引量:1
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作者 Cuixiang Zhong 《Journal of Physical Science and Application》 2019年第2期17-25,共9页
Nebula theory is the most widely accepted hypothesis about the formation and evolution of the Solar System. This theoryholds that the Sun is formed from a collapsed gas cloud 4.57 billion years ago;when the core tempe... Nebula theory is the most widely accepted hypothesis about the formation and evolution of the Solar System. This theoryholds that the Sun is formed from a collapsed gas cloud 4.57 billion years ago;when the core temperature of the gas cloud rises to 10million K, the thermonuclear reaction of hydrogen fusion into helium is ignited, then the Sun become a star;once the hydrogen in thecore is exhausted, the life of the star will end. But the limited hydrogen element obviously cannot satisfy such a long-termthermonuclear reaction, in order to sustain long-term thermonuclear reactions, a steady stream of fuel must be obtained from space.So the existing hypothesis about the formation and evolution of the Solar System has serious defects. Thus the author has studied theformation of the Moon, the Earth and the Sun, and discovered the formation of the Sun and the real source of star energy. The authorcould also explain many solar activity phenomena such as sunspots, flares, prominences, etc. 展开更多
关键词 Sun FORMATION EVOLUTION star energy sunspotS flares.
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STUDY ON RELATIONS BETWEEN HEAVY-DISASTER-PERIOD OF FOREST FIRE ACTIVITY AND SUNSPOT ACTIVITY, SSTA
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作者 王述洋 宋国育 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第4期27-32,共6页
The HDPFF (heavy-disaster-period of forest fire) takes up 1 / 4-1 / 3 of all observation years, but the loss takes up 80-90% of all. The author studied the relations between forest fire activity in Heilongiiang Provin... The HDPFF (heavy-disaster-period of forest fire) takes up 1 / 4-1 / 3 of all observation years, but the loss takes up 80-90% of all. The author studied the relations between forest fire activity in Heilongiiang Province from 1950 to 1989 and activity of sunspot, SSTA (sea surface temperature abnormality) of the North Pacific Ocean. The study discovered that : (1 )there was a negative correlation between forest fire condition in Heilongjiang Province and annual average of sunspot relative numbers, furthermore, the heavy-disaster-period was prone to occur in valley year and the next year; (2) SSTA in the North Pacific Ocean markedly influenced the forest fire activity and the level of its conditions in Heilongjiang province. 展开更多
关键词 Forest fire Heavy-disaster-period sunspot ACTIVITY Sea surface temperature abnormality
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THE FRACTAL RESEARCH AND PREDICATING ON THE TIME SERIES OF SUNSPOT RELATIVE NUMBER
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作者 顾圣士 王志谦 程极泰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第1期84-89,共6页
In this paper, with the theory of nonlinear dynamic systems, It is analyzed that the dynamic behavior and the predictabilityfor the monthly mean variationsof the sunspot relative number recorded from January 1891 to D... In this paper, with the theory of nonlinear dynamic systems, It is analyzed that the dynamic behavior and the predictabilityfor the monthly mean variationsof the sunspot relative number recorded from January 1891 to December 1996. Inthe progress, the fractal dimension (D = 3. 3±0. 2) for the variation process wascomputed. This helped us to determine the embedded dimension [2×D + 1] = 7.By computing the Lyapunov index (λ1 = 0. 863), it was indicated that the variationprocess is a chaotic system. The Kolmogorov entropy (K = 0.0260) was also computed, which provides, theoretically, the predicable time scale. And at the end,according to the result of the analysis above, an experimental predication is made,whose data was a part cut from the sample data. 展开更多
关键词 NUMBER of sunspotS FRACTAL dimension KOLMOGOROV entropy Lyapunov NUMBER PREDICATE
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Sunspot rotation and magnetic transients associated with flares in NOAAAR 11429
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作者 Jian-Chuan Zheng Zhi-Liang Yang +4 位作者 Jian-Peng Guo Kai-Ming Guo Hui Huang Xuan Song Wei-Xing Wan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第8期47-56,共10页
We analyze sunspot rotation and magnetic transients in NOAA AR 11429 during two X-class(X5.4 and X1.3)flares using data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory.A large leading... We analyze sunspot rotation and magnetic transients in NOAA AR 11429 during two X-class(X5.4 and X1.3)flares using data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory.A large leading sunspot with positive magnetic polarity rotated counterclockwise.As expected,the rotation was significantly affected by the two flares.Magnetic transients induced by the flares were clearly evident in the sunspots with negative polarity.They were moving across the sunspots with speed of order 3-7 km s^(-1).Furthermore,the trend of magnetic flux evolution in these sunspots exhibited changes associated with the flares.These results may shed light on understanding the evolution of sunspots. 展开更多
关键词 sunspotS - Sun: ROTATION - Sun: MAGNETIC fields
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CORRELATION ANALYSIS OF FOREST FIRES AND SUNSPOTS
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作者 Wang Shuyang Zhang Yanli Luo ShumeiNortheast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1992年第2期54-58,共5页
This paper analyses the relationship of forest fires and sunspots in Heilongjiang Province in the past 40 years(1950—1989).The results indicated that each of the forest fire in-dexes such as forest fire rate(Y1),time... This paper analyses the relationship of forest fires and sunspots in Heilongjiang Province in the past 40 years(1950—1989).The results indicated that each of the forest fire in-dexes such as forest fire rate(Y1),times of forest fire(Y2),average forest fire area for one time Y4(equals the Y5/Y2)and total forest fire area(Y5)has a negatlve correlation with mean annual relative sunspots of the same year;total times of forest fire inside and outside of forest stands(Y3)bus a positive correlation with sunspots The 5 indexes stated above has a similar re-lation to last year’s mean annual relative sunspots. 展开更多
关键词 FOREST FIRE sunspot RELATIONSHIP
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Spatial distributions of sunspot oscillation modes at different temperatures
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作者 Zheng-Kai Wang Song Feng +1 位作者 Lin-Hua Deng Yao Meng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第1期43-48,共6页
Three-and five-minute sunspot oscillations have different spatial distributions in the solar atmospheric layers.The spatial distributions are crucial for revealing the physical origin of sunspot oscillations and to in... Three-and five-minute sunspot oscillations have different spatial distributions in the solar atmospheric layers.The spatial distributions are crucial for revealing the physical origin of sunspot oscillations and to investigate their propagation.In this study,six sunspots observed by Solar Dynamics Observatory/Atmospheric Imaging Assembly were used to obtain the spatial distributions of three-and five-minute oscillations.The fast Fourier transform method is applied to represent the power spectra of oscillation modes.We find that,from the temperature minimum to the lower corona,the powers of the fiveminute oscillation exhibit a circle-shape distribution around its umbra,and the shapes gradually expand with temperature increase.However,the circle-shape disappears and the powers of the oscillations appear to be very disordered in the higher corona.This indicates that the five-minute oscillation can be suppressed in the high-temperature region.For the three-minute oscillations,from the temperature minimum to the high corona,their powers mostly distribute within an umbra,and part of them are located at the coronal fan loop structures.Moreover,those relative higher powers are mostly concentrated in the position of coronal loop footpoints. 展开更多
关键词 Sun:atmosphere Sun:sunspots Sun:oscillations
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Chinese sunspot drawings and their digitization–(Ⅲ)quasi-biennial oscillation of the hand-drawn sunspot records
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作者 Miao Wan Shu-Guang Zeng +1 位作者 Sheng Zheng Gang-Hua Lin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第11期354-360,共7页
Quasi-biennial Oscillations(QBOs)of the Sun have a significant meaning as a benchmark of solar cycle,not only for understanding the dynamo action but also in terms of space weather prediction.In this paper,the hand-dr... Quasi-biennial Oscillations(QBOs)of the Sun have a significant meaning as a benchmark of solar cycle,not only for understanding the dynamo action but also in terms of space weather prediction.In this paper,the hand-drawn sunspot images recorded from the Purple Mountain Observatory are used to investigate the solar QBOs and the Gnevyshev gap of the sunspot relative numbers(Rs)and group sunspot numbers(Rg)during the period 1954–2011.The main results are as follows:(1)both the Rs and Rg exhibit similar periods including the 22-year magnetic cycle,the 11-year Schwabe cycle,and the QBOs modes;(2)the reconstructed QBOs of both data sets exhibit coherent behavior and tend to have a high amplitude during the maximum phase of each solar cycle;(3)the Gnevyshev gap is produced by the superposition of the QBOs and the 11-year Schwabe cycle,and the Rs is better to study the variation of the Gnevyshev gap rather than the Rg. 展开更多
关键词 SUN activity SUN sunspot SUN quasi-biennial oscillation
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Chinese sunspot drawings and their digitization–(Ⅱ)accuracy analysis for digitized sunspot hand-drawing records of Yunnan Observatories
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作者 Yang Peng Xiao-Yu Luo +6 位作者 Shu-Guang Zeng Lin-Hua Deng Sheng Zheng Gang-Hua Lin Yu-Lin Cheng Jin-Ping Tao Yong-Li Feng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第4期156-162,共7页
Sunspots are the most striking and easily observed magnetic structures of the Sun,and statistical analysis of solar historical data could reveal a wealth of information on the long-term variation of solar activity cyc... Sunspots are the most striking and easily observed magnetic structures of the Sun,and statistical analysis of solar historical data could reveal a wealth of information on the long-term variation of solar activity cycle.The hand-drawn sunspot records of Yunnan Observatories,Chinese Academy of Sciences have been accumulating for more than 60 years,and nearly 16000 images have been preserved.In the future,the observation mode of recording sunspots by hand-drawing will be replaced inevitably by digital images observed either at ground or in space.To connect the hand-drawn sunspot data and the purely digital sunspot data in future,it is necessary to analyze the systematic errors of the data which are observed by the two observation modes in the period of transition.In this paper,we choose 268 round sunspots(Htype in modified Zurich sunspot classification)from the drawing of Yunnan Observatories to compare their positions and areas with the CCD observations made by Helioseismic and Magnetic Imager(HMI)on board Solar Dynamic Observatory(SDO)and Global Oscillation Network Group(GONG).We find that the latitude and longitude accuracy of hand-drawn sunspot are within-0.127 and 2.29 degree respectively,and the area accuracy is about 16.36 sunspot unit(μHem).Systematic errors apparently decrease with large sunspot. 展开更多
关键词 sunspotS methods:data analysis techniques:image processing
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Chinese Sunspot Drawings and Their Digitization—(Ⅶ) Sunspot Penumbra to Umbra Area Ratio Using the Hand-Drawing Records from Yunnan Observatories
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作者 Jia-Wei Hou Shu-Guang Zeng +7 位作者 Sheng Zheng Xiao-Yu Luo Lin-Hua Deng Yang-Yang Li Yan-Qing Chen Gang-Hua Lin Yong-Li Feng Jin-Ping Tao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第9期132-139,共8页
The ratio of penumbral to umbra area of sunspots plays a crucial role in the solar physics fields, especially for understanding the origin and evolution of the solar activity cycle. By analyzing the recently digitized... The ratio of penumbral to umbra area of sunspots plays a crucial role in the solar physics fields, especially for understanding the origin and evolution of the solar activity cycle. By analyzing the recently digitized sunspot drawings observed from Yunnan Observatories(1957–2021), we investigate the long-term variation of the penumbral to umbra area ratio of sunspots. An automatic extraction method, based on the maximum between-class variance and the morphological discrimination, is used to accurately extract penumbra and umbra and to calculate the ratio over six solar cycles(cycle 19–24). The expected value of the ratio of penumbra to umbra area is found to be 6.63 ± 0.98, and it does not exhibit any systematic variation with sunspot latitudes and phases. The average ratio fluctuates from 5 to 7.5 per year and the overall trend has decreased after 1999 compared to the previous one.The ratio of sunspot penumbra to umbra area satisfies the log-normal distribution, implying that its variation is related to the evolution of the photospheric magnetic field. Our results are consistent with previous works. 展开更多
关键词 Sun:sunspots Sun:photosphere Sun:activity techniques:image processing
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Effects of Sunspot on the Multi-Decadal Climate Projections
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作者 ZHAO Zong-Ci LUO Yong HUANG Jian-Bin 《Advances in Climate Change Research》 SCIE 2014年第1期51-56,共6页
Most model generated projections of climate change for the future decades only consider anthropogenic activities.It is hard to think about the effects of solar activity and volcano effects,because the predictions of b... Most model generated projections of climate change for the future decades only consider anthropogenic activities.It is hard to think about the effects of solar activity and volcano effects,because the predictions of both solar activity and volcano effects are difficult.But as we know,the sun is the source of energy for the Earth’s climate system,and 展开更多
关键词 RCP Effects of sunspot on the Multi-Decadal Climate Projections QBO cycle CESM Figure
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Inter-correlation between Sunspot Oscillations and Their Internal Structures
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作者 Libo Fu Zizhan Zhu +3 位作者 Ding Yuan Jiaoyang Wang Song Feng Sergey Anfinogentov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第11期97-106,共10页
Three-and five-minute oscillations are commonly observed in any sunspot.Because they are modulated by the internal thermal and magnetic structures of a sunspot,they could be used as an effective tool for researching s... Three-and five-minute oscillations are commonly observed in any sunspot.Because they are modulated by the internal thermal and magnetic structures of a sunspot,they could be used as an effective tool for researching sunspot seismology.In this paper,we investigate the properties of oscillations in sunspot groups with varying sizes and magnetic fields,and aim to establish the relationships between sunspot oscillations and its internal structure comparatively.We selected three groups of the unipolar sunspot with approximately axial-symmetric magnetic field and calculated their Fourier spectra based on the ultraviolet/extreme ultraviolet emission intensity variations recorded by the Solar Dynamics Observatory/Atmospheric Imaging Assembly.We found that the distribution of three-minute oscillation is defined by the joint effect of diverging magnetic field and the stratification of the sunspot atmosphere.Its distribution could be modified by any invading magnetic structures in the umbra.In contrast,the five-minute oscillations are more prominent in small spots,implying that five-minute oscillation is very closely connected with umbral dynamics. 展开更多
关键词 (Sun:)sunspots Sun:oscillations methods:data analysis
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Predictions of Galapagos Volcanic Eruption, El Niño, Ecuadorian Earthquake, Global Volcanic Eruption and Forest Fire by Sunspot Number
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作者 Tai-Jin Kim 《Natural Science》 2020年第1期12-27,共16页
The earthquake number was correlated (R2 = 0.8781) with the volcano number in the East Pacific and Central American countries. The year of volcanic eruptions in the Galapagos Hot Spot (GHS) was proportional to the yea... The earthquake number was correlated (R2 = 0.8781) with the volcano number in the East Pacific and Central American countries. The year of volcanic eruptions in the Galapagos Hot Spot (GHS) was proportional to the year of El Ni&#241o events (R2 = 0.9939) as well as to the year of earthquake events (R2 = 0.9943) in Ecuador, Colombia, and Peru from 1977 to 2016. Therefore, there can be El Ni&#241o and earthquake events in Ecuador, Colombia and Peru if there are strong volcanic eruptions either from aboveground volcanoes or undersea seamounts in the GHS during the maximal sunspot number’s period. Global volcanic eruptions were occurred during the maximal temperature departure, the latter being reversely proportional (R2 = 0.4512) to the sunspot number from 1980 to 2019. Forest fires occurred in middle latitude countries (South Korea, California, western Russia, Australia) around 35 degree from Pacific Equator during La Ni&#241a events at the time of the minimal sunspot number. Since there were intense forest fires in South Korea, Australia and California in 2019, more are expected in 2030 due to the 11 year cyclical variation in the sunspot number. The sequence of forest fires can be schematically summarized as below. 1) La Ni&#241a event in Equator causes the low vapor pressure of water due to the low sea surface temperature (SST);2) There is the pumping of freshwater from the warm Pacific Ocean to cold Equator with simultaneous transfer of heat (warm Pacific Ocean to cold Equator) and mass (water enriched Pacific Ocean to water lean Equator);3) Strong winds from dry zone pass Mountains to cause the forest fires in the residential land with bushes and trees. 4) According to the Bernoulli’s principle, the pressure gradient between the high Mountains and the low Ocean, induces the decrease of static velocity gradient for vigorously upwards flares in the Mountains and the residential land during the forest fires, which may be why it is difficult to extinguish the forest fires until burnt up bushes and trees in the Mountains and residential land with serious damages. Most effective solution to forest fires is to change the events from La Ni&#241a to El Ni&#241o for reductions of temperature and pressure gradients by Gay-Lussac’s law. Such a transition may be induced by artificial submarine volcanic eruptions among volcanoes of Fernandina, Sierra Negra and Wolf in the GHS for Korea and California. As for Australia, artificial volcanic eruptions can be caused in huge underwater volcano chain in Tasmania. The strong damages of forest fires in South Korea, Australia and California were observed in the period of the minimal sunspot number, as were in October of 2019 to February of 2020. Simultaneous transfers of momentum (velocity), heat (temperature) and mass (freshwater) were occurred from the dry zone or the hot Deserts via the Mountains and the residential land with bushes and trees to the cold Sea or Ocean. It is expected the lowest SST during the year of the minimal sunspot number to induce the strong damages of forest fires, as was in South Korea, Australia and California during the years from 2019 to 2020. CO2 emissions in Australia showed 34.5% increase, 70% coal power and no nuclear power to induce bushfires because of increases of ozone hole area and UV radiation for the hot land in the period of La Ni&#241a. Fossil fuel operation should be cut down to decrease the ozone hole area and UV radiation for weak bushfires in Australia. A few coming years may still have bushfires in Australia although their damages may not be as terrible as was in 2020. A simple remedy can be the reduction of CO2 emissions as low as possible. It was proposed that the maximal sunspot number induced El Ni&#241o event, GHS volcanic eruption and Ecuadorian earthquakes, while the minimal sunspot number induced La Ni&#241a events in Ecuador, Colombia, Peru and intense forest fires in middle latitude countries of South Korea (forest fires), Australia (bushfires) and California (wildfires). 展开更多
关键词 Prediction VOLCANIC ERUPTION Ecuadorian EARTHQUAKE FOREST Fire sunspot Number
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Periodic variation and phase analysis of grouped solar flare with sunspot activity
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作者 Hui Deng Ying Mei Feng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第2期75-84,共10页
Studies on the periodic variation and the phase relationship between different solar activity indicators are useful for understanding the long-term evolution of solar activity cycles.Here we report the statistical ana... Studies on the periodic variation and the phase relationship between different solar activity indicators are useful for understanding the long-term evolution of solar activity cycles.Here we report the statistical analysis of grouped solar flare(GSF) and sunspot number(SN) during the time interval from January 1965 to March 2009.We find that,(1) the significant periodicities of both GSF and SN are related to the differential rotation periodicity,the quasi-biennial oscillation(QBO),and the eleven-year Schwabe cycle(ESC),but the specific values are not absolutely identical;(2) the ESC signal of GSF lags behind that of SN with an average of 7.8 months during the considered time interval,which implies that the systematic phase delays between GSF and SN originate from the inter-solar-cycle signal.Our results may provide evidence about the storage of magnetic energy in the corona. 展开更多
关键词 Sun:sunspots Sun:flares Sun:activity Sun:magnetic fields
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