Field-aligned irregularities generated in and around the auroral oval

Field-aligned plasma density observations from the Poker Flat Incoherent Scatter Radar (PFISR) near Fairbanks, Alaska are used to provide new insights into the creation and evolution of high latitude F-region irregularities. We analyze the diurnal variation of plasma density and its temporal evolution throughout the day. The day-to-day variability is influenced to some extent by geomagnetic activity, with decreases in the AL index (SML index) corresponding to an increase in density, particularly around midnight. These negative correlations do not always occur simultaneously, with the time lag between these events requiring further investigation. We also look at the statistical distribution of plasma density median and quartiles at every half hour Magnetic Local Time (MLT) interval around solstices and equinoxes. Seasonal variations in plasma density depend on the sunlit period and changes throughout different years. We analyze the plasma density data measured in different years during period of high solar activity (F10.7 > 100) and low solar activity (F10.7 < 100). This statistical study shows that plasma density is enhanced and has small interquartile range during higher solar activity period. At times of low solar activity, the overall median plasma density is depleted with significant drop in first quartile contributing to larger interquartile range around dawn and dusk. This presentation discusses these findings in more detail.