The use of spread F and sporadic E observations in interplanetary scintillation forecasts of geomagnetic activity

Previous work has shown that interplanetary scintillation (IPS) observations produce a poor forecast for geomagnetic activity. An explanation of some of the problems encountered would be the existence of an additional scintillation signal, e.g. of ionospheric origin. Hoping to reduce the effect of any ionospheric activity, and hence improve the forecast, local ionospheric observations were used in selecting IPS data. The success of geomagnetic forecasts based on these data was calculated, in this case by correlating the scintillation level with Ap. The coefficient at one day lag increased from 0.40±0.04 to 0.62±0.05, but did not represent a significant improvement in forecast quality since the data were heavily biased towards periods of low Ap