Publication Date:
2024-04-23
Description:
A new analytical formula for H0, one of the three parameters (H0, g, and r) on which the
NeQuick model is based to describe the altitude profile of the electron density above the F2-layer
peak height hmF2, has recently been proposed. This new analytical representation of H0, called
H0,corr, relies on numerical grids based on two different types of datasets. On one side, electron density
observations by the Swarm satellites over Europe from December 2013 to September 2018, and
on the other side, IRI UP (International Reference Ionosphere UPdate) maps over Europe of the
critical frequency of the ordinary mode of propagation associated with the F2 layer, foF2, and hmF2,
at 15 min cadence for the same period. The new NeQuick topside representation based on H0,corr,
hereafter referred to as NeQuick-corr, improved the original NeQuick topside representation. This
work updates the numerical grids of H0,corr by extending the underlying Swarm and IRI UP datasets
until December 2021, thus allowing coverage of low solar activity levels, as well. Moreover, concerning
Swarm, besides the original dataset, the calibrated one is considered, and corresponding
grids of H0,corr calculated. At the same time, the role of g is investigated, by considering values different
from the reference one, equal to 0.125, currently adopted. To understand what are the best
H0,corr grids to be considered for the NeQuick-corr topside representation, vertical total electron content
data for low, middle, and high latitudes, recorded from five low-Earth-orbit satellite missions
(COSMIC/FORMOSAT-3, GRACE, METOP, TerraSAR-X, and Swarm) have been analyzed. The updated
H0,corr grids based on the original Swarm dataset with a value for g = 0.15, and the updated
H0,corr grids based on the calibrated Swarm dataset with a value for g = 0.14, are those for which the
best results are obtained. The results show that the performance of the different NeQuick-corr models
is reliable also for low latitudes, even though these are outside the spatial domain for which the
H0,corr grids were obtained, and are dependent on solar activity.
Description:
Published
Description:
498
Description:
OSA3: Climatologia e meteorologia spaziale
Description:
JCR Journal
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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