A Long‐Term Data Set of Vertical Ion Drift Velocity at High Latitudes Constructed From DMSP Measurements

Observations of vertical ion drift velocities (V-z) at the topside of the ionosphere by Defense Meteorological Satellite Program (DMSP) satellites have been accumulated over decades and provide us a unique opportunity to study the vertical ion drifts through the ionosphere on different temporal and spatial scales. In this paper, V-z data of F13, which are of high quality, are taken as the reference to rescale the measurements of DMSP F11, F12, F14, F15, and F16 at high latitudes from 50 degrees N/S to 90 degrees N/S, which show significant differences from each other in magnitudes. Through rescaling, all V-z data of F11-F16 are in a similar order of magnitudes. Moreover, their spatial and temporal distributions resemble each other on average and are consistent with the excepted averaged behaviors reported in previous studies. Thus, the rescaling is basically effective, which provides an opportunity to construct a data set of V-z from 1995 to 2014 that covers nearly two solar cycles for further statistical analysis. Meanwhile, it should be noted that the rescaling results are qualitative/semiqualitative with some uncertainty, which needs more detailed discussion and analysis in future studies.