3-D time varying GPS imaging of the polar ionosphere.

Project: Engineering and Physical Sciences Research Council

Researcher: Paul Spencer / Ping Yin

Imaging the polar cap ionosphere presents a number of unique problems which are not usually encountered when imaging other regions of the Earth's near space environment.  The sparsity of  data sources as well as the complex physics of the region requires the development of new imaging techniques which combine available data with the latest models of the polar cap electric and magnetic fields.  The motion of plasma in the polar cap is largely controlled by the ExB drift associated with the strong electric fields over the polar regions.  These fields are themselves related to the strength and orientation of the interplanetary magnetic field (IMF).  The imaging technique currently in development aims to use this estimate of the plasma motion to better interpolate between the available data.

Colours show the electric field potential over the polar cap with the vectors showing the resulting ExB drift velocity.  Local midday is towards the left of the image.