North-south asymmetry in global distribution of the solar wind speed during 1985–2013
Interplanetary scintillation (IPS) observations made between 1985 and 2013 are used to investigate the north-south (N-S) asymmetry in global distribution of the solar wind speed. The IPS observations clearly demonstrate that the global distribution of the solar wind speed systematically changes with...
Published in: | Journal of Geophysical Research: Space Physics |
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Online Access: | http://hdl.handle.net/2237/24210 https://doi.org/10.1002/2014JA020765 https://nagoya.repo.nii.ac.jp/record/22151/files/Tokumaru_et_al-2015-Journal_of_Geophysical_Research_Space_Physics.pdf |
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ftnagoyauniv:oai:nagoya.repo.nii.ac.jp:00022151 2023-05-15T17:39:59+02:00 North-south asymmetry in global distribution of the solar wind speed during 1985–2013 Tokumaru, Munetoshi 65720 Fujiki, Ken'ichi 65721 Iju, Tomoya 65722 2015-05 application/pdf http://hdl.handle.net/2237/24210 https://doi.org/10.1002/2014JA020765 https://nagoya.repo.nii.ac.jp/record/22151/files/Tokumaru_et_al-2015-Journal_of_Geophysical_Research_Space_Physics.pdf eng eng AGU publications https://doi.org/10.1002/2014JA020765 Journal of Geophysical Research: Space Physics 5 120 3283 3296 http://doi.org/10.1002/2014JA020765 http://hdl.handle.net/2237/24210 2169-9380 https://nagoya.repo.nii.ac.jp/record/22151/files/Tokumaru_et_al-2015-Journal_of_Geophysical_Research_Space_Physics.pdf ©2015. American Geophysical Union. All Rights Reserved. Global observations of the solar wind including high-latitude regions Heliospheric response to long-term change in the solar dynamo activity Marked north-south asymmetry of the polar solar wind and its origin 2015 ftnagoyauniv https://doi.org/10.1002/2014JA020765 2023-02-20T14:39:26Z Interplanetary scintillation (IPS) observations made between 1985 and 2013 are used to investigate the north-south (N-S) asymmetry in global distribution of the solar wind speed. The IPS observations clearly demonstrate that the global distribution of the solar wind speed systematically changes with the solar activity. This change is found to closely correlate with that in polar magnetic fields of the Sun, while fast wind data at solar minima systematically deviate from this correlation. The IPS observations show that notable N-S asymmetry of polar solar winds occurs at the solar maxima, and small but significant N-S asymmetry exists at the solar minima. The observed asymmetry at the solar maxima is consistent with the time lag in the reversal of polar magnetic fields between north and south hemispheres. We also find that significant N-S asymmetry of the polar fast wind lasts for the period between Cycles 23 and 24 solar maxima, starting from predominance of the fast wind over the north pole and ending with that over the south pole. The N-S asymmetry revealed from IPS observations is found to be generally consistent with Ulysses observations. We compare IPS observations with magnetic field data of the Sun and find that the ratio of the quadrupole to dipole coefficients exhibits a similar time variation to that of the N-S asymmetry revealed from IPS observations. This suggests that higher-order multipole moments play an important role in determining the N-S asymmetry of the solar wind when the dipole moment weakens. journal article Other/Unknown Material North Pole South pole Nagoya University: NAGOYA Repository North Pole South Pole Journal of Geophysical Research: Space Physics 120 5 3283 3296 |
institution |
Open Polar |
collection |
Nagoya University: NAGOYA Repository |
op_collection_id |
ftnagoyauniv |
language |
English |
topic |
Global observations of the solar wind including high-latitude regions Heliospheric response to long-term change in the solar dynamo activity Marked north-south asymmetry of the polar solar wind and its origin |
spellingShingle |
Global observations of the solar wind including high-latitude regions Heliospheric response to long-term change in the solar dynamo activity Marked north-south asymmetry of the polar solar wind and its origin Tokumaru, Munetoshi 65720 Fujiki, Ken'ichi 65721 Iju, Tomoya 65722 North-south asymmetry in global distribution of the solar wind speed during 1985–2013 |
topic_facet |
Global observations of the solar wind including high-latitude regions Heliospheric response to long-term change in the solar dynamo activity Marked north-south asymmetry of the polar solar wind and its origin |
description |
Interplanetary scintillation (IPS) observations made between 1985 and 2013 are used to investigate the north-south (N-S) asymmetry in global distribution of the solar wind speed. The IPS observations clearly demonstrate that the global distribution of the solar wind speed systematically changes with the solar activity. This change is found to closely correlate with that in polar magnetic fields of the Sun, while fast wind data at solar minima systematically deviate from this correlation. The IPS observations show that notable N-S asymmetry of polar solar winds occurs at the solar maxima, and small but significant N-S asymmetry exists at the solar minima. The observed asymmetry at the solar maxima is consistent with the time lag in the reversal of polar magnetic fields between north and south hemispheres. We also find that significant N-S asymmetry of the polar fast wind lasts for the period between Cycles 23 and 24 solar maxima, starting from predominance of the fast wind over the north pole and ending with that over the south pole. The N-S asymmetry revealed from IPS observations is found to be generally consistent with Ulysses observations. We compare IPS observations with magnetic field data of the Sun and find that the ratio of the quadrupole to dipole coefficients exhibits a similar time variation to that of the N-S asymmetry revealed from IPS observations. This suggests that higher-order multipole moments play an important role in determining the N-S asymmetry of the solar wind when the dipole moment weakens. journal article |
author |
Tokumaru, Munetoshi 65720 Fujiki, Ken'ichi 65721 Iju, Tomoya 65722 |
author_facet |
Tokumaru, Munetoshi 65720 Fujiki, Ken'ichi 65721 Iju, Tomoya 65722 |
author_sort |
Tokumaru, Munetoshi |
title |
North-south asymmetry in global distribution of the solar wind speed during 1985–2013 |
title_short |
North-south asymmetry in global distribution of the solar wind speed during 1985–2013 |
title_full |
North-south asymmetry in global distribution of the solar wind speed during 1985–2013 |
title_fullStr |
North-south asymmetry in global distribution of the solar wind speed during 1985–2013 |
title_full_unstemmed |
North-south asymmetry in global distribution of the solar wind speed during 1985–2013 |
title_sort |
north-south asymmetry in global distribution of the solar wind speed during 1985–2013 |
publisher |
AGU publications |
publishDate |
2015 |
url |
http://hdl.handle.net/2237/24210 https://doi.org/10.1002/2014JA020765 https://nagoya.repo.nii.ac.jp/record/22151/files/Tokumaru_et_al-2015-Journal_of_Geophysical_Research_Space_Physics.pdf |
geographic |
North Pole South Pole |
geographic_facet |
North Pole South Pole |
genre |
North Pole South pole |
genre_facet |
North Pole South pole |
op_relation |
https://doi.org/10.1002/2014JA020765 Journal of Geophysical Research: Space Physics 5 120 3283 3296 http://doi.org/10.1002/2014JA020765 http://hdl.handle.net/2237/24210 2169-9380 https://nagoya.repo.nii.ac.jp/record/22151/files/Tokumaru_et_al-2015-Journal_of_Geophysical_Research_Space_Physics.pdf |
op_rights |
©2015. American Geophysical Union. All Rights Reserved. |
op_doi |
https://doi.org/10.1002/2014JA020765 |
container_title |
Journal of Geophysical Research: Space Physics |
container_volume |
120 |
container_issue |
5 |
container_start_page |
3283 |
op_container_end_page |
3296 |
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1766140755625115648 |