In situ magnetospheric observations and the corresponding data collected at the foot of the field line in the ionosphere can together form an invaluable tool for studying the processes involved in magnetosphere-ionosphere coupling provided the mappings between various regions in the magnetosphere and ionosphere are precisely known. A multivariable analysis technique is used to identify spatially localized modes of oscillations in the ionospheric plasma velocities monitored at F region heights by the Goose Bay HF radar. The temporal variations of these modes are compared with the magnetic fluctuations recorded by the AMPTE CCE satellite which was within the magnetic latitude-longitude region monitored by the radar. It is possible to clearly identify spatially localized modes in the ionosphere with temporal variations that track the azimuthal oscillations observed in the magnetosphere. This analysis approach offers a powerful method for establishing mappings between different regions of the magnetosphere and ionosphere under widely varying background conditions. The method, which is applied here exclusively to the mapping problem, can also be used to identify the natural modes of magnetospheric oscillation. ¿ American Geophysical Union 1992