We introduce the implementation of a global climatological model of the equatorial ionospheric F-region zonal drifts (EZDrifts) that is made available to the public. The model uses the analytic description of the zonal plasma drifts presented by Haerendel et al. (1992) [ J Geophys Res 97(A2) : 1209–1223] and is driven by climatological models of the ionosphere and thermosphere under a realistic geomagnetic field configuration. EZDrifts is an expansion of the model of the zonal drifts first presented by Shidler & Rodrigues (2021) [ Prog Earth Planet Sci 8 : 26] which was only valid for the Jicamarca longitude sector and two specific solar flux conditions. EZDrifts now uses vertical equatorial plasma drifts from Scherliess & Fejer (1999) [ J Geophys Res 104(A4) : 6829–6842] model which allows it to provide zonal drifts for any day of the year, longitude, and solar flux condition. We show that the model can reproduce the main results of the Shidler & Rodrigues (2021) [ Prog Earth Planet Sci 8 : 26] model for the Peruvian sector. We also illustrate an application of EZDrifts by presenting and discussing longitudinal variabilities produced by the model. We show that the model predicts longitudinal variations in the reversal times of the drifts that are in good agreement with observations made by C/NOFS. EZDrifts also predicts longitudinal variations in the magnitude of the drifts that can be identified in the June solstice observations made by C/NOFS. We also point out data-model differences observed during Equinox and December solstice. Finally, we explain that the longitudinal variations in the zonal plasma drifts are caused by longitudinal variations in the latitude of the magnetic equator and, consequently, in the wind dynamo contributing to the resulting drifts. EZDrifts is distributed to the community through a public repository and can be used in applications requiring an estimate of the overall behavior of the equatorial zonal drifts.
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This content will become publicly available on April 1, 2027
A New Global Climatological Model of the Equatorial Ionospheric Vertical E × B Drift: Integrating Ground‐Based Magnetometer, Radar, and Satellite Data Sets
Abstract We present a new empirical vertical drift model developed using ground‐based magnetometer, radar, and satellite data over equatorial latitude regions. We first implement an algorithm relating magnetometer derived equatorial electrojet (EEJ) and vertical ion plasma drift (equivalent to vertical drift within magnetic latitudes of and altitudes of about 400–550 km) from the Communications and Navigation Outage Forecasting System (C/NOFS) satellite at different longitude sectors. The relationship between EEJ and C/NOFS vertical drift is developed separately at different longitudes over the globe at coincidental times when both data sets are available. These relationships are then used to estimate continuous vertical drift at each epoch of EEJ observation over the respective longitude sectors during local daytime. The reconstructed vertical drift data are combined with global C/NOFS vertical drifts and JULIA data set to develop a global vertical drift model. Validation using Ion Velocity Meter (IVM) drifts from ICON satellite for January to August 2022 shows that our model improves vertical drift global modeling by over 20% compared to the current climatology representation.
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- PAR ID:
- 10694716
- Publisher / Repository:
- AGU
- Date Published:
- Journal Name:
- Earth and Space Science
- Volume:
- 13
- Issue:
- 4
- ISSN:
- 2333-5084
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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