A new short-term forecasting model for the total electron content storm time disturbances

Abstract

-This paper aims to introduce a new model for the short-term forecast of the vertical Total Electron Content (vTEC). The basic idea of the proposed model lies on the concept of the Solar Wind driven autoregressive model for Ionospheric short-term Forecast (SWIF). In its original version, the model is operationally implemented in the DIAS system (http://dias.space.noa.gr) and provides alerts and warnings for upcoming ionospheric disturbances, as well as single site and regional forecasts of the foF2 critical frequency over Europe up to 24 h in advance. The forecasts are driven by the real time assessment of the solar wind conditions at ACE location. The comparative analysis of the variations in foF2 and vTEC during eleven geomagnetic storm events that occurred in the present solar cycle 24 reveals similarities but also differences in the storm-time response of the two characteristics with respect to the local time and the latitude of the observation point. Since the aforementioned dependences drive the storm-time forecasts of the SWIF model, the results obtained here support the upgrade of the SWIF's modeling technique in forecasting the storm-time vTEC variation from its onset to full development and recovery. According to the proposed approach, the vTEC storm-time response can be forecasted from 1 to 12-13 h before its onset, depending on the local time of the observation point at storm onset at L1. Preliminary results on the assessment of the performance of the proposed model and further considerations on its potential implementation in operational mode are also discussed.

One‐ to 10‐Day Forecasts of Ionospheric Total Electron Content Using a Statistical Model

“…This is because the minimal autocorrelation of the geomagnetic activity indices precludes their autoregressive forecasting. Current state‐of‐the‐art techniques for forecasting geomagnetic activity utilize independent observations of coronal mass ejections and their perturbation of the ambient solar wind speed and density (e.g., Tsagouri et al, ). The SWPC does provide 3‐day forecasts of ap ; whether use of these forecasts improves the statistical model's TEC forecasts requires further analysis analogous to that described here using the EUV irradiance forecasts, if independent ap and Dxt forecasts are available over the past two decades.…”

“…The European Digital Upper Atmosphere Server uses ground‐based observations to specify electron density peak heights and concentrations over Europe (Belehaki et al, ). Twenty‐four‐hour forecasts incorporating models of solar wind impacts to estimate prospective geomagnetic influences demonstrate improved forecast skill relative to persistence and climatology (Tsagouri, ; Tsagouri et al, ).…”

Space Weather Effects on the Earth’s Upper Atmosphere: Short Report on Ionospheric Storm Effects at Middle Latitudes

“…Moreover, positive storm effects at higher latitudes in case the observation point at storm onset time is located in the morning sector were present only for TEC. The TEC positive phase was more intense in the lower latitudes, especially in the afternoon hours [67].…”

An overview of methodologies for real-time detection, characterisation and tracking of traveling ionospheric disturbances developed in the TechTIDE project

“…In practice, the STD map reflects the standard deviations of the values taken into account in the calculation of the corresponding medians at each point of the grid. In this respect, b that represents the relative STD (%) aims to delimit the normal ionospheric variability (Tsagouri et al, 2018b(Tsagouri et al, , 2018c. Ionospheric effects at each pixel of the map (i, j, k) are characterised as "median" when |a| |b|, as "positive" when |a| > |b| and a > 0 and as "negative" when |a| > |b| and a < 0.…”