Open AccessA Bayesian Inference‐Based Empirical Model for Scintillation Indices for High‐Latitude
Author(s) -
Meziane K.,
Kashcheyev A.,
Jayachandran P. T.,
Hamza A. M.
Publication year - 2021
Publication title -
space weather
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.254
H-Index - 56
ISSN - 1542-7390
DOI - 10.1029/2020sw002710
Subject(s) - interplanetary scintillation , solar wind , interplanetary magnetic field , scintillation , earth's magnetic field , geodesy , physics , environmental science , meteorology , geology , coronal mass ejection , magnetic field , optics , quantum mechanics , detector
Solar wind parameters, the solar radio flux index (F10.7), the Sun's declination and the SuperMAG Electrojet index are used to construct a Bayesian inference‐based empirical model for scintillation indices ( S 4 and σ Φ ) at high latitudes. For the present study, measurements from three Global Positioning System (GPS) L 1 receivers located in the auroral zone, the cusp and in the polar cap are selected, respectively. The solar wind characteristics include the solar wind speed ( V SW ) and ram pressure ( ρ SW ) as well as the Geocentric Solar Magnetospheric (GSM) B y and the B z components of the interplanetary magnetic field (IMF). Following a brief assessment on the independence of the variables (predictors), prior probabilities of occurrence in the case of a multinomial classification are constructed. Posterior‐probabilities are then deduced for any arbitrary set of predictors. We show that the model captures most variations seen in the measured indices whether they are associated or not with transient interplanetary events. Although the model tends to underestimate the actual phase index measurements, 95% of the validated events are predicted with an error less than 0.034 rad in σ Φ . For the amplitude scintillation index, 5% of validated events have an error larger than 0.019.