Kp forecast models

Abstract

[1] Magnetically active times, e.g., Kp > 5, are notoriously difficult to predict, precisely the times when such predictions are crucial to the space weather users. Taking advantage of the routinely available solar wind measurements at Langrangian point (L1) and nowcast Kps, Kp forecast models based on neural networks were developed with the focus on improving the forecast for active times. To satisfy different needs and operational constraints, three models were developed: (1) a model that inputs nowcast Kp and solar wind parameters and predicts Kp 1 hour ahead; (2) a model with the same input as model 1 and predicts Kp 4 hour ahead; and (3) a model that inputs only solar wind parameters and predicts Kp 1 hour ahead (the exact prediction lead time depends on the solar wind speed and the location of the solar wind monitor). Extensive evaluations of these models and other major operational Kp forecast models show that while the new models can predict Kps more accurately for all activities, the most dramatic improvements occur for moderate and active times. Information dynamics analysis of Kp suggests that geospace is more dominated by internal dynamics near solar minimum than near solar maximum, when it is more directly driven by external inputs, namely solar wind and interplanetary magnetic field (IMF).

Two methods to forecast auroral displays

“…Auroral activity Level The index is predicted every 15 min by the use of the Wing Kp Predicted Activity Index model (Wing et al 2005), which takes into account the most recent estimated Kp values and the response of solar wind parameters (neural network algorithm).…”

“…When the input data come from a satellite located approximately 1 h upstream in the solar wind, the resultant predicted Kp forecast is relatively short term (Costello 1997;Wing et al 2005). It gives a 1-or 4-h warning.…”

Identification and replacement of proton‐contaminated real‐time ACE solar wind measurements

“…Previous studies have demonstrated that the solar wind and IMF are the drivers for geomagnetic activity and can be used to predict geomagnetic activity [e.g., Wing et al, 2005;Fung and Shao, 2008;and Bala and Reiff, 2012]. To select a solar wind speed proxy, we examine correlations of solar wind speed with several measures of geomagnetic activity: the auroral electrojet index (AE), Kp, and the polar cap potential (PC).…”

“…For example, the solar wind speed and magnetic field components are used at SWPC as model inputs to predict the Kp index, a measure of global magnetic disturbances [Wing et al, 2005].…”

Progress in space weather modeling in an operational environment

“…(ii) The Global D-Region Absorption Product addresses the operational impact of the solar X-ray flux and SEP events on HF radio communication, providing a global map of the highest frequency affected by absorption of 1 dB due to either solar X-ray flux or SEP events or a combination of both, an attenuation bar graph, status messages, and an estimated recovery clock. -Geomagnetic Predictions: The Wing Kp Predicted Geomagnetic Activity Index model (Wing et al 2005) provides 1 h and 4 h predictions of the Kp index. -Satellite Environments Predictions: The Relativistic Electron Forecast Model (REFM) predicts the >2 MeV 24-h electron fluence at geo-synchronous orbit.…”