关键词: 极区,地磁场,电流体系,电导率

Abstract:

The current systems representing the solar and lunar daily variations (S and L)of the geomagnetic field have been calculated on the basis of the date obtained from the global network of geomagnetic observatories.The characteristics of these current systems in the Antarctic and Arctic regions have been analysed comparatively. The results show that:(1)There are certain differences in the current systems of these two regions,that implies definite differences in the ionospheric dynamo process,responsible for both S and L,and the field-aligned current,responsible for S.The differences of the magnetic field structure in these two polar regions may be the basic reason of the above mentioned differences.(2)There are remarkable differences in the internal current systems of these two polar regions,that is attributed to both the inducing field ( current) and the underground conductivity.In general,the conductivity of the Antarctic region is higher than that of the Arctic region.