Prediction of solar activities:Sunspot numbers and solar magnetic synoptic maps  

作　　者：Rui ZHUO Jiansen HE Die DUAN Rong LIN Ziqi WU Limei YAN Yong WEI 

机构地区：[1]School of Earth and Space Sciences,Peking University,Beijing 100091,China [2]College of Advanced Interdisciplinary Studies,National University of Defense Technology,Changsha 410073,China [3]Centre for Mathematical Plasma Astrophysics,Department of Mathematics,KU Leuven,Leuven 3001,Belgium [4]Key Laboratory of Earth and Planetary Physics,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China [5]College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Science China Earth Sciences》2024年第8期2460-2477,共18页中国科学（地球科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.42241118,42174194,42150105,42204166,42241106,42074207);the National Key R&D Program of China(Grant Nos.2021YFA0718600,2022YFF0503800);the CNSA(Grant No.D050106);supported by Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2021064)。

摘　　要：The evolution of solar magnetic fields is significant for understanding and predicting solar activities.And our knowledge of solar magnetic fields largely depends on the photospheric magnetic field.In this paper,based on the spherical harmonic expansion of the photospheric magnetic field observed by Wilcox Solar Observatory,we analyze the time series of spherical harmonic coefficients and predict Sunspot Number as well as synoptic maps for Solar Cycle 25.We find that solar maximum years have complex short-period disturbances,and the time series of coefficient g_(7)~0 is nearly in-phase with Sunspot Number,which may be related to solar meridional circulation.Utilizing Long Short-Term Memory networks(LSTM),our prediction suggests that the maximum of Solar Cycle 25 is likely to occur in June 2024 with an error of 8 months,the peak sunspot number may be 166.9±22.6,and the next solar minimum may occur around January 2031.By incorporating Empirical Mode Decomposition,we enhance our forecast of synoptic maps truncated to Order 5,validating their relative reliability.This prediction not only addresses a gap in forecasting the global distribution of the solar magnetic field but also holds potential reference value for forthcoming solar observation plans.

关 键 词：Solar activity prediction Solar magnetic field Spherical harmonic expansion Long-Short Term Memory(LSTM) Empirical Mode Decomposition(EMD) 

分 类 号：P182.9[天文地球—天文学]