@article{oai:nipr.repo.nii.ac.jp:00006335, author = {Nakano,Shin'ya and Iyemori ,Toshihiko}, journal = {Advances in polar upper atmosphere research}, month = {Sep}, note = {P(論文), The magnetic local time (MLT) dependence of magnetic variations on the ground at mid-latitudes caused by field-aligned currents is estimated for two cases where the distribution of the field-aligned currents is defined at the magnetosphere and at the polar ionosphere. The results show that the MLT distribution of the magnetic variations shifts eastward or westward by a few hours in the latter case because the terrestrial magnetic field declines from the geographic meridian. Whether the distribution shifts eastward or westward depends on the longitude of the observatory. This fact suggests that whether the distribution of a phenomenon propagating along the terrestrial magnetic field is mainly determined in the magnetosphere or in the ionosphere may be determined by comparing the MLT distribution of the phenomenon's magnetic effect at observatories located at various longitudes.}, pages = {128--134}, title = {Longitudinal dependence of eastward and westward magnetic variations at mid-latitudes}, volume = {15}, year = {2001} }