A COMPARISON BETWEEN 2 CORRECTED GEOMAGNETIC COORDINATE SYSTEMS AT HIGH-LATITUDES

The existing corrected geomagnetic coordinate system is based on internal sources of the Earth's magnetic field and describes observed phenomena in a time-independent way. Space experiments, however, use universal time to follow the dynamics of observed phenomena in 3-dimensional space and external sources play an important role there. A new corrected coordinate system based on the ''realistic'' geomagnetic equator is proposed to order observations of experiments at each moment of time. The system is based on constant B-minimum ovals at the 3-D geomagnetic equator plane. The magnetospheric model by TSYGANENKO (1989) is used and an algorithm has been developed to derive the lines of constant latitude at ionospheric heights for a specific universal time. Combining these latitudes with corrected geomagnetic longitudes provides an opportunity to order polar ionospheric phenomena in accordance with their ''realistic'' positions near footpoints of geomagnetic field lines. An attempt is made to interpret some results from the PACE radar experiment using the calculated latitude ovals.