INTECIN   20395
INSTITUTO DE TECNOLOGIAS Y CIENCIAS DE LA INGENIERIA "HILARIO FERNANDEZ LONG"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Spectral studies of time series of AA index and sunspot numbers
Autor/es:
P.L.LAROCCA; V.M.SILBERGLEIT; A.L.CLUA DE GONZALEZ
Lugar:
Ubatuba, Brasil
Reunión:
Congreso; ILWS – International living with a star 2009; 2009
Institución organizadora:
NASA, FAPESP, CNPq, INPE
Resumen:
<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:595.3pt 841.9pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> It is well known that the frecuency and intensity of terrestrial magnetic disturbances, when examined statistically, exhibits some clear periods, such as the sunspot cycle variation of about eleven years. Our first aim in this report is to study the periodicity in geomagnetic activity using monthly aa index and monthly sunsppot number for a big period of time 1868-2008. We use Discrete Fourier Transforms to find some new periodicities and confirm the known ones. We have confirmed that solar activity and geomagnetic index have the common cyclic variations of 2; 3.5 ; 5.5 and 11 years.