Abstract
We analyzed ground magnetometer data for the 10 International Quiet Days during 1996-2007. The data were obtained from 19 stations along 210°magnetic meridian (MM) of the Circum-pan Pacific Magnetometer Network (CPMN) covering both the Northern Hemisphere and Southern Hemisphere. From the daily variations of the geomagnetic field, we deduced the latitude-local time (LAT-LT) diagram of the equivalent Sq current system, which can be regarded as the superposition of the following three current systems: Sqo, Sq 1, and Sq2. The Sq0, Sq1, and Sq2 current systems are equivalent current systems for the yearly average, annual variation, and semiannual variation of the Sq field, respectively. We have examined temporal and spatial features of these current systems. The principal features are as follows: (1) The total current intensities of the Sq1 and Sq2 current systems are about 35% and 15% of that of the Sq0 current system, respectively. (2) The Sq0 and Sq2 current systems have a dayside vortex in each hemisphere, while the Sq1 current system has a single vortex centered at the equatorial region in the morning sector (∼1000 LT).
Original language | English |
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Article number | A12320 |
Journal | Journal of Geophysical Research: Space Physics |
Volume | 114 |
Issue number | 12 |
DOIs | |
Publication status | Published - Jan 1 2009 |
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- Geophysics
- Forestry
- Oceanography
- Aquatic Science
- Ecology
- Water Science and Technology
- Soil Science
- Geochemistry and Petrology
- Earth-Surface Processes
- Atmospheric Science
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science
- Palaeontology
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Equivalent current systems for the annual and semiannual Sq variations observed along the 210°MM CPMN stations. / Yamazaki, Y.; Yumoto, K.; Uozumi, T.; Yoshikawa, Akimasa; Cardinal, M. G.
In: Journal of Geophysical Research: Space Physics, Vol. 114, No. 12, A12320, 01.01.2009.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Equivalent current systems for the annual and semiannual Sq variations observed along the 210°MM CPMN stations
AU - Yamazaki, Y.
AU - Yumoto, K.
AU - Uozumi, T.
AU - Yoshikawa, Akimasa
AU - Cardinal, M. G.
PY - 2009/1/1
Y1 - 2009/1/1
N2 - We analyzed ground magnetometer data for the 10 International Quiet Days during 1996-2007. The data were obtained from 19 stations along 210°magnetic meridian (MM) of the Circum-pan Pacific Magnetometer Network (CPMN) covering both the Northern Hemisphere and Southern Hemisphere. From the daily variations of the geomagnetic field, we deduced the latitude-local time (LAT-LT) diagram of the equivalent Sq current system, which can be regarded as the superposition of the following three current systems: Sqo, Sq 1, and Sq2. The Sq0, Sq1, and Sq2 current systems are equivalent current systems for the yearly average, annual variation, and semiannual variation of the Sq field, respectively. We have examined temporal and spatial features of these current systems. The principal features are as follows: (1) The total current intensities of the Sq1 and Sq2 current systems are about 35% and 15% of that of the Sq0 current system, respectively. (2) The Sq0 and Sq2 current systems have a dayside vortex in each hemisphere, while the Sq1 current system has a single vortex centered at the equatorial region in the morning sector (∼1000 LT).
AB - We analyzed ground magnetometer data for the 10 International Quiet Days during 1996-2007. The data were obtained from 19 stations along 210°magnetic meridian (MM) of the Circum-pan Pacific Magnetometer Network (CPMN) covering both the Northern Hemisphere and Southern Hemisphere. From the daily variations of the geomagnetic field, we deduced the latitude-local time (LAT-LT) diagram of the equivalent Sq current system, which can be regarded as the superposition of the following three current systems: Sqo, Sq 1, and Sq2. The Sq0, Sq1, and Sq2 current systems are equivalent current systems for the yearly average, annual variation, and semiannual variation of the Sq field, respectively. We have examined temporal and spatial features of these current systems. The principal features are as follows: (1) The total current intensities of the Sq1 and Sq2 current systems are about 35% and 15% of that of the Sq0 current system, respectively. (2) The Sq0 and Sq2 current systems have a dayside vortex in each hemisphere, while the Sq1 current system has a single vortex centered at the equatorial region in the morning sector (∼1000 LT).
UR - http://www.scopus.com/inward/record.url?scp=77954332943&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77954332943&partnerID=8YFLogxK
U2 - 10.1029/2009JA014638
DO - 10.1029/2009JA014638
M3 - Article
AN - SCOPUS:77954332943
VL - 114
JO - Journal of Geophysical Research
JF - Journal of Geophysical Research
SN - 0148-0227
IS - 12
M1 - A12320
ER -