Variability of Solar Irradiances Using Wavelet Analysis
Abstract
We have used wavelets to analyze the sunspot number, F10.7 (the solar irradiance at a wavelength of 10.7~cm), and Ap (a geomagnetic activity index). Three different wavelets are compared, showing how each selects either temporal or scale resolution. Our goal is an envelope of solar activity that better bounds the large amplitude fluctuations form solar minimum to maximum. We show how the 11-year cycle does not disappear at solar minimum, that minimum is only the other part of the solar cycle. Power in the fluctuations of solar-activity-related indices may peak during solar maximum but the solar cycle itself is always present. The Ap index has a peak after solar maximum that appears to be better correlated with the current solar cycle than with the following cycle.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- Bibcode:
- 2007AGUFMSH13A1100P
- Keywords:
-
- 3270 Time series analysis (1872;
- 4277;
- 4475);
- 3280 Wavelet transform (3255;
- 4455);
- 7536 Solar activity cycle (2162);
- 7538 Solar irradiance