HIGH-LATITUDE PLASMA CONVECTION - PREDICTIONS FOR EISCAT AND SONDRE STROMFJORD

We have used a plasma convection model to predict diurnal patterns of horizontal drift velocities in the vicinity of the EISCAT incoherent scatter facility at TromsoNorway and for Sondre StromfjordGreenlanda proposed new incoherent scatter facility site. The convection model includes the offset of 11.4° between the geographic and geomagnetic poles (northern hemisphere)the tendency of plasma to corotate about the geographic poleand a magnetospheric electric field mapped to a circle about a center offset by 5° in the antisunward direction from the magnetic pole. Four different magnetospheric electric field configurations were consideredincluding a constant cross‐ tail electric fieldasymmetric electric fields with enhancements on the dawn and dusk sides of the polar capand an electric field pattern that is not aligned parallel to the noon‐midnight magnetic meridian. The different electric field configurations produce different signatures in the plasma convection pattern which are clearly identified. Both of these high‐latitude sites are better suited to study magnetospheric convection effects than either ChatanikaAlaska or Millstone HillMassachusetts. Alsoeach site appears to have unique capabilities with regard to studying certain aspects of the magnetospheric electric field. Copyright 1979 by the American Geophysical Union.