@article{oai:nipr.repo.nii.ac.jp:00006284,
 author = {Nagatsuma, Tsutomu and Obara, Takahiro and Ishibashi, Hiromitsu and Hayashi, Kanji and McEwen, Donald J.},
 journal = {Advances in polar upper atmosphere research},
 month = {Sep},
 note = {P(論文), Solar wind electric field that penetrates into the magnetosphere is an important key for causes of magnetosphenc disturbances. Since PC index, produced from the variation of the magnetic field in the near-pole regions is known to be a good indicator of magnetospheric electric field, monitoring the magnetic activity in the near-pole regions in real-time is useful for nowcasting/forecasting space weather. From the comparison of horizontal components of the magnetic field data between two stations, Eureka and Thule, it is found that the correlation between these two stations are quite high except for the summer months. This result suggests that magnetic field variations in the near-pole region are uniform, and the index can be produced throughout the year using magnetic field data in the northern and southern near-pole region.},
 pages = {132--138},
 title = {Real-time monitor of geomagnetic field in the near-pole regions as an index of magnetospheric electric field},
 volume = {13},
 year = {1999}
}