The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo
There are some indications that the coupling function between the polar and the toroidal solar magnetic field strengths are time dependent. Therefore, as proxy data of these strengths, the relationship between long-term modulation of solar and geomagnetic activity is analyzed here by means of a wave...
Guardado en:
| Autores principales: | , |
|---|---|
| Formato: | JOUR |
| Materias: | |
| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_00948276_v29_n13_p6_Duhau |
| Aporte de: |
| id |
todo:paper_00948276_v29_n13_p6_Duhau |
|---|---|
| record_format |
dspace |
| spelling |
todo:paper_00948276_v29_n13_p6_Duhau2023-10-03T14:56:28Z The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo Duhau, S. Chen, Ch.Y. Magnetic fields Modulation Oscillations Phase shift Sunspot number Geomagnetism geomagnetic field solar activity sunspot There are some indications that the coupling function between the polar and the toroidal solar magnetic field strengths are time dependent. Therefore, as proxy data of these strengths, the relationship between long-term modulation of solar and geomagnetic activity is analyzed here by means of a wavelet multi-resolution analysis of yearly means of sunspot number and geomagnetic index aa since 1844. It is found that aa index and relative sunspot number long-term modulations oscillate around constant levels that have increased to be 1.9 and 1.6, respectively of its values prior 1923. The oscillations of the aa and Rz long-term modulation appear to be well represented by the superposition of a decadal cycle and the Gleissberg cycle. The amplitude ratio and the phase shift between the Rz and aa decadal cycles changed sharply at year 1923, and the Gleissberg cycle was interrupted to be restarted at year 1949. The synchronicity of these changes with temporal changes in several solar and solar-terrestrial variables indicates that the non-linear nature of the solar dynamo has lead to a major change of its background state after 1923. Fil:Duhau, S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00948276_v29_n13_p6_Duhau |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Magnetic fields Modulation Oscillations Phase shift Sunspot number Geomagnetism geomagnetic field solar activity sunspot |
| spellingShingle |
Magnetic fields Modulation Oscillations Phase shift Sunspot number Geomagnetism geomagnetic field solar activity sunspot Duhau, S. Chen, Ch.Y. The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo |
| topic_facet |
Magnetic fields Modulation Oscillations Phase shift Sunspot number Geomagnetism geomagnetic field solar activity sunspot |
| description |
There are some indications that the coupling function between the polar and the toroidal solar magnetic field strengths are time dependent. Therefore, as proxy data of these strengths, the relationship between long-term modulation of solar and geomagnetic activity is analyzed here by means of a wavelet multi-resolution analysis of yearly means of sunspot number and geomagnetic index aa since 1844. It is found that aa index and relative sunspot number long-term modulations oscillate around constant levels that have increased to be 1.9 and 1.6, respectively of its values prior 1923. The oscillations of the aa and Rz long-term modulation appear to be well represented by the superposition of a decadal cycle and the Gleissberg cycle. The amplitude ratio and the phase shift between the Rz and aa decadal cycles changed sharply at year 1923, and the Gleissberg cycle was interrupted to be restarted at year 1949. The synchronicity of these changes with temporal changes in several solar and solar-terrestrial variables indicates that the non-linear nature of the solar dynamo has lead to a major change of its background state after 1923. |
| format |
JOUR |
| author |
Duhau, S. Chen, Ch.Y. |
| author_facet |
Duhau, S. Chen, Ch.Y. |
| author_sort |
Duhau, S. |
| title |
The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo |
| title_short |
The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo |
| title_full |
The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo |
| title_fullStr |
The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo |
| title_full_unstemmed |
The sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo |
| title_sort |
sudden increase of solar and geomagnetic acitivity after 1923 as a manifestation of a non-linear solar dynamo |
| url |
http://hdl.handle.net/20.500.12110/paper_00948276_v29_n13_p6_Duhau |
| work_keys_str_mv |
AT duhaus thesuddenincreaseofsolarandgeomagneticacitivityafter1923asamanifestationofanonlinearsolardynamo AT chenchy thesuddenincreaseofsolarandgeomagneticacitivityafter1923asamanifestationofanonlinearsolardynamo AT duhaus suddenincreaseofsolarandgeomagneticacitivityafter1923asamanifestationofanonlinearsolardynamo AT chenchy suddenincreaseofsolarandgeomagneticacitivityafter1923asamanifestationofanonlinearsolardynamo |
| _version_ |
1782024111757721600 |