2011 SuperDARN Workshop       

On the relationship of polar cap flow velocities and the IMF/solar wind

W.A. Bristow, J. Spaleta, T. Parris
UAF Geophysical Institute

abstract. At nearly 80 degrees magnetic latitude, the SuperDARN radar at McMurdo is the highest latitude radar in the network. The distance from the radar to the magnetic pole is about 1000 km, which is an ideal range for observations of F-region irregularities. The high incidence of irregularities in the polar cap has yielded an excellent database of polar cap velocity observations. This study draws from this database to examine the relationship between the observed Earth-Sun component of the flows and the IMF and solar wind. Line-of-sight velocity observations from latitude greater than 85 degrees magnetic were used when the dot product of the radar k-vector and the Earth-Sun direction exceeded 0.9. Time series of the velocities were correlated with the IMF z-component and found that on average the correlation is about 50%. In some intervals the correlation exceeded 80% while in others there was virtually no correlation. Scatter plots of the observations show a roughly linear relationship between Bz and the velocity, however the spread about the line was significant.

Sakaguchi KaoriNICT Japan