Probabilistic forecasts of ionospheric low-latitude scintillation using an ensemble data assimilation model

Abstract

A proxy for vertical plasma drift (PVPD) at the magnetic equator can be used as an indicator of whether strong ionospheric scintillation will occur at low-latitudes. Using this approach with a physics-based model has previously been shown to demonstrate forecasting skill. AENeAS is an ensemble data assimilation model with a physics-based background. In this work scintillation forecasting using the mean of the AENeAS ensemble is shown to increase forecasting skill when compared to forecasting with a deterministic physics-based model. AENeAS is also used to create probabilistic forecasts by generating an ensemble of PVPDs. Using kernel density estimation these PVPDs are combined to form a probability density function of the PVPD speed. The probability of strong scintillation occurring can then be determined. This method can be applied at a range of longitudes on the magnetic equator, thereby providing a global, probabilistic, early warning forecast of low-latitude scintillation.