Evaluating the forecast performance of Total Electron Content from first-principles models

Abstract:

To understand the forecast capability of first-principles ionospheric and thermospheric models, we conduct “forecast-mode” simulations, by definition relying only on input quantities that can be obtained ahead of time from forecasted solar wind conditions and solar irradiance. We have analyzed more than 30 geomagnetic storms via the Community Coordinated Modeling Center (CCMC) using three different models: 1) the Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics Model (CTIPe); 2) the Global Ionosphere-Thermosphere Model (GITM); and 3) the Thermosphere Ionosphere Electrodynamics General Circulation Model (TIE-GCM). The inputs for each of the models include the forecasted solar 10.7 cm wavelength flux (F10.7) and observed solar wind conditions. CTIPe additionally takes forecasted hemispheric power indices. The geomagnetic storm events in the study cover a variety of storms, such as storms caused by high-speed solar wind streams and coronal mass ejections, storms occurring at different phases of the solar cycle, and storms with various strengths. The forecasted ionospheric total electron content (TEC) maps are analyzed with a metric that quantifies the global and local TEC responses and compared to TEC responses derived from Global Positioning System observations. The performance of the three ionospheric models CTIPe, GITM, and TIE-GCM are summarized via the forecast success rate, providing insights into the model capabilities in forecasting ionospheric space weather.