Forecasting the ionospheric response to solar wind forcing: Suggestive results obtained through the evaluation of the performance of the Solar Wind driven autoregressive model for Ionospheric short-term Forecast (SWIF)

Abstract:

The SWIF model (Solar Wind driven autorgressive model for Ionospheric short-term Forecast) was developed in the National Observatory of Athens to support ionospheric forecasting services for the users of DIAS (http://dias.space.noa.gr) and ESA-Space Situational Awareness Space Weather Service Network (http://swe.ssa.esa.int/). The model was originally designed to provide forecasts of the foF2 critical frequency, including alerts and warnings for upcoming ionospheric disturbances, as well as single site and regional forecasts up to 24 hours ahead. Very recently, SWIF was upgraded to expand its forecasting capabilities to the total electron content (TEC) ionospheric characteristic.

SWIF is driven by interplanetary magnetic field (IMF) observations (IMF-total magnitude and IMF-Bz) obtained in real time at L1 point. In this respect, the model provides an alternative approach to ionospheric forecasting issue, using solar wind parameters as a proxy of the geomagnetic activity level and therefore, a unique platform for investigating present forecasting capabilities with respect to solar wind drivers. Indeed, the performance of the model has been tested over a wide range of disturbed space weather conditions, from moderate to intense in the previous and present solar cycle. The evaluation results give evidence of quite successful performance under the occurrence of CME related disturbances, while the model's performance is significantly lower in case of HSSs/CIR related disturbances. The latter indicates strong limitations to our present forecasting abilities and the requirement for more efficient drivers from solar wind environment and/or more sophisticated descriptions of the ionospheric response for forecasting purposes especially. This task becomes important in periods of low solar activity as the one approaching and crucial in extreme solar minimum conditions. This presentation aims to summarize relevant results, showing also possible alternatives than IMF parameters (e.g. solar wind density and velocity, energy input to the magnetosphere), with an eye on the advantage these alternatives can bring in expanding the ionospheric forecasting window to several days in advance. This analysis will be driven by present solar wind forecasting capabilities to account for realistic suggestions.