Ionization enhancement from Van Allen electrons in the South Atlantic Magnetic Anomaly

Satellite particle observations have shown that a longitudinal dependence exists for trapped electrons at B-L points extending into the lower atmosphere over the South Atlantic anomaly. The longitudinal variation results from the precipitation and loss of trapped particles drifting through the anomaly and is a regular characteristic of the Van Allen radiation zones. The trapped electrons that collide with atmospheric constituents produce ionization and represent a significant source of local enhancements in the D and lower E regions of the ionosphere. Regions where electron-ion augmentations may be expected are also discussed.