Influence Of Sunspots Number On Geomagnetic Activity And Climate Change

Solar activity has a great influence on the whole process of the dynamics of the earth system。Disturbances caused by solar activity affect the earth’s magnetic field changes, in the form of the electromagnetic radiation and the solar wind and enhanced solar cosmic rays。Therefore, the research on the relationship between solar activity and geomagnetic activity has important implications for predicting the happening of the geomagnetic disturbance, avoiding and reducing the influence of geomagnetic disturbance。The sun throw energy to the atmosphere and the surface of the earth by thermal radiation effects in each frequency band, causing the change of weather and climate including atmospheric circulation and ocean circulation.Therefore, the research on the relationship between the solar activity and climate change not only help to better understand the solar-terrestrial relationship and climate rhythms,but also develop the new methods of weather forecast.This article mainly aims at studying the influence of sunspots number on geomagnetic activity and climate change,using wavelet method and empirical mode decomposition(EMD) method and ensemble empirical mode decomposition(EEMD) method, analyze periodic characteristics of the sunspots number,the geomagnetic Ap index and the East Asian summer monsoon(EASM)index,get the following results:(1)A11of wavelet method,empirical mode decomposition method and ensemble empirical mode decomposition method have advantages in signal processing.But in the analysis of month average of sunspots number and geomagnetic Ap index,wavelet analysis results show the inconsistency; also in the decomposition experiment,wavelet analysis appears nonexistent component while the empirical mode decomposition is truly restore the frequency components of the signal data.In the analysis of the east Asian summer monsoon index, empirical mode decomposition method shows high accuracy and stability; while ensemble empirical mode decomposition is also obtained similar results with the use of empirical mode decomposition method.(2)Using the EMD method,the averages of monthly,seasonal,yearly of the sunspot number can be decomposed into a series of modes and a trend respectively,among them,the11-year solar cycle mode with the largest amplitude has the high correlations with original sunspot numbers.(3)Using the EMD method,the averages of monthly,seasonal,yearly of the geomagnetic Ap index can be decomposed into a series of modes and a trend respectively,among them,the11-year solar cycle mode with the largest amplitude has the high correlations with original the geomagnetic Ap index.(4)A11of the sunspot activity,the EASM activity and the geomagnetic activity have the same cycle component of11-year。According to the comparison of the sunspot number, the geomagnetic Ap index and the EASM index, we get that Geomagnetic Ap index extremum lagged the sunspot number extremum about1years, and the EASM index extremum lagged the geomagnetic Ap index about1.7years, this shows that the solar activity influences the geomagnetic activity, and the geomagnetic activity influences the EASM on the interdecadal time scale.