Three‐dimensional measurements of traveling ionospheric disturbances with the Poker Flat Incoherent Scatter Radar

In this paper, we present results from the Advanced Modular Incoherent Scatter Radar (AMISR) installed at the Poker Flat Research Range near Fairbanks, Alaska, the Poker Flat Incoherent Scatter Radar (PFISR), that focus on the ability of the system to make three‐dimensional, simultaneous measurements of ionospheric parameters. We present observations from PFISR where we were able to resolve the three components of the k vector of a traveling ionospheric disturbance (TID), as well as the period. These measurements give insight into the atmospheric gravity wave (AGW)‐TID relationship, allowing us to apply a recently developed dispersion relation for AGWs that includes the role of kinematic viscosity and thermal diffusivity, important effects in the upper atmosphere, without assumptions about horizontal wavelengths. The analysis indicates that for this particular case, the wave must have been propagating against a background wind of ∼125 m/s. PFISR will be a powerful tool for studying the sources and propagation of waves in the upper atmosphere.