Transition over maximum of superlong solar cycle at present in mathematical model of solar activity using the last data as input to climate changes
Abstract
We calculated a new version of mathematical model of solar activity by a method of non-linear spectral analysis called by the method of global minimum. We used for calculation of the new version of the model data set the last data of annual Wolf sunspot numbers W, for the period 1700 - 2001 yr. It is found, that the most of sinusoids with high level of statistical significance are non-stationary ones (with varying phase and amplitude). It is possible to see from its time changes the temporary boundaries of trains of waves and phase catastrophes on these boundaries. The non-linear mechanism of generation of these cycles is shown. A sinusoid with period of about 2000 yr. and a super-secular non-stationary harmonic with period 130 yr present the long-term part of the spectrum. The secular cycle is represented by a non-stationary harmonic with period 60 years. The magnetic cycle is described by a non-stationary harmonics with period 22.36 yr. Long-periodic non-stationary harmonic with T = 35 yr. is possibly connected with well-known Briekner's cycle. The main peak of the solar cycle in this version is a non-stationary sine wave at period 10.80 yr. The non-stationary harmonics with the following periods in years are obtained also: 8.59 6.58; 5.36; 5.21. The forecasting the future course of the 23 cycle is given. The comparison of this polyharmonic model with our previous models calculated on the basis of shorter data length is presented. Time changes of the super-secular component of all calculated models shows that the long-period growth of solar activity from the beginning of the last century has been finished. We observe for now the beginning of the transition of the solar activity to the next secular minimum. Besides, spectrum of Wolf numbers, apparently, consists of the separate spectral bands. These bands consist of a few close maxima (the bands of frequencies of these maxima are often greater than 1/T). When we calculate more and more accurate models, we derive various maxima from the indicated bands. The reality of these maxima is confirmed by the fact that the other authors using the other spectral methods obtained the same periods. We see also periodic appearance of the same periods in different versions of our models (calculated on the basis of different data sets of W). Supersecular component of solar activity in this version is presented by periods 241, 246, 204 years. The main peak of solar activity represented by two spectral peaks at T=11.1 yr. and T=10.7 yr. in our previous models is represented by a non-stationary harmonics with T = 10.8 years in this new model (data for the period 1700-2001). Annual Wolf number is known at this moment for 2002 yr. We’ll present too more accurate model of the solar activity taking into account this value that will allow forecasting the development of the current cycle of 23 more reliably.
- Publication:
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EGS - AGU - EUG Joint Assembly
- Pub Date:
- April 2003
- Bibcode:
- 2003EAEJA.....2316T