Equatorial disturbance dynamo plasma drifts and neutral winds over Jicamarca

The equatorial ionosphere undergoes large and long lasting changes following geomagnetic storms. We use incoherent scatter radar and JULIA observations from the Jicamarca Radio Observatory to study the variability of equatorial disturbance dynamo drifts. This mechanism drives relatively small downward/eastward drifts from about sunrise to sunset with largest magnitudes near dusk. The nighttime disturbance dynamo drifts are upward and westward with large magnitudes in the post-midnight sector. We show that these drifts increase from solar minimum to solar maximum, particularly near dusk, and have largest magnitudes during equinox. We also compare the Jicamarca disturbance dynamo vertical drifts with observations from ROCSAT-1. We also examine the relationship between the Jicamarca nighttime zonal disturbance drifts and Fabry-Perot measured neutral wind disturbances, and compare our data with results from numerical simulations.