Evaluating Auroral Forecasts Against Satellite Observations Under Different Levels of Geomagnetic Activity

• Published in: Journal of geophysical research. Space physics 2024-08, Vol.129 (8), p.n/a
• Main Authors: Mooney, M. K., Forsyth, C., Marsh, M. S., Bradley, L., Finnigan, T., Forde, F., Garrigan, F., Mancini‐Tuffier, C., Mancini‐Tuffier, T., Roberts, E., Vessoni, P., Powell, J., Clark, S., Lao, C. J., Smith, A., Jackson, D. R., Bingham, S., Sharpe, M., Hughes, T., Chisham, G., Milan, S.
• Format: Article
• Language: English
• Subjects: Auroral activity; Auroral emissions; auroral forecasting; Auroral oval; Auroras; Aviation; Communication networks; Communications networks; Defense industry; Disruption; Earth magnetosphere; Emergency warning programs; Emission analysis; Emissions; Equatorial regions; forecast verification; Forecasting models; Geomagnetic activity; Geomagnetism; Image enhancement; Latitude; OVATION‐prime 2013; Performance evaluation; Performance prediction; Polar caps; Radio communications; ROC scores; Satellite imagery; Satellite observation; Satellites; Space weather; truth table; Weather forecasting; Weather hazards
• ISSN: 2169-9380; 2169-9402
• DOI: 10.1029/2023JA031478

The aurora and associated high energy particles and currents pose a space weather hazard to communication networks and ground‐based infrastructure. Forecasting the location of the auroral oval forms an integral component of daily space weather operations. We evaluate a version of the OVATION‐Prime 2013 auroral forecast model that was implemented for operational use at the UK Met Office Space Weather Operations Cent. Building on our earlier studies, we evaluate the ability of the OVATION‐Prime 2013 model to predict the location of the auroral oval in all latitude and local time sectors under different levels of geomagnetic activity, defined by Kp. We compare the model predictions against auroral boundaries determined from IMAGE FUV data. Our analysis shows that the model performs well at predicting the equatorward extent of the auroral oval, particularly as the equatorward auroral boundary expands to lower latitudes for increasing Kp levels. The model performance is reduced in the high latitude region near the poleward auroral boundary, particularly in the nightside sectors where the model does not accurately capture the expansion and contraction of the polar cap as the open flux content of the magnetosphere changes. For increasing levels of geomagnetic activity (Kp ≥ 3), the performance of the model decreases, with the poleward edge of the auroral oval typically observed at lower latitudes than forecast. As such, the forecast poleward edge of the auroral oval is less reliable during more active and hazardous intervals. Plain Language Summary Enhanced auroral activity can be hazardous to technology and essential daily services at Earth. The aurora can cause disruption to communication networks including long‐range radio communications and induce currents in the ground which can impact electricity supply networks. A version of the OVATION‐Prime 2013 auroral forecast model is commonly used in space weather forecast centers to predict the occurrence and location of the aurora, providing advanced warning of possible disruption to stakeholder industries in the aviation, defense and energy sectors. In this study, we perform a detailed evaluation of the performance of this model by comparing the auroral forecasts against satellite observations of the aurora from the IMAGE satellite. Our analysis shows that the model performs well at predicting the location of the main auroral emission, particularly the extent of the auroral emission to lower latitudes with increas