Joint Study Group

Atmospheric Coupling Studies

Led by ICCT; joint with GGOS FAGSWR and IAG Commission 4, Sub-Commission 4.3

Chair: Andres Calabia Aibar (Spain)
Vice-Chair: Binod Adhikari (Nepal)


The connection between solar drivers and the Earth’s magnetosphere, ionosphere/plasmasphere, and thermosphere (MIT) phenomena in the upper atmosphere is very complex and dependent on many processes, including energy-absorption, ionization, and dissociation of molecules due to variable X-ray and Extreme Ultra Violet (EUV) solar radiance. Moreover, the variable solar wind plasma combined with a favorable alignment of the Interplanetary Magnetic Field (IMF) can produce auroral particle precipitation at high latitudes, causing enhanced chemical reactions, electric currents, and Joule heating. The primary objective of JSG4 is to enhance our understanding of the interactions between solar wind and Earth, including atmospheric coupling processes within the MIT and the lower atmosphere.

Consequences of the upper atmosphere conditions on human activity underscore the necessity to better understand and predict atmospheric coupling processes and prevent society from detrimental impacts on existing technologies. For instance, the propagation of electromagnetic radio waves employed by satellite communication systems depend on the spatial gradients of charged particles in the ionosphere (mostly free-moving electrons), and unforeseen anomalies can perturb technologies based on, for example, Remote Sensing (RS) or GNSS measurement data. Another impact on society involves the expansion/contraction of the atmosphere in response to the variable solar activity, producing aerodynamic drag perturbations on LEO satellites, and making satellite tracking difficult, decelerating LEO orbits, reducing their altitude, and shortening the lifespan of space assets.

Figure 4.1: Known processes in the coupled MIT system. Credits: NASA’s Scientific Visualization Studio

Therefore, the primary goal of JSG4 is to enhance our understanding of the interactions between solar wind and Earth, including the coupling processes within the MIT system. In addition, waves from the lower atmosphere including atmospheric tides and planetary waves can feed into ionospheric electrodynamics, and consequently to the MIT system. For instance, gravity waves can deposit momentum in the upper atmosphere, and change the mean state which then influences the wave propagation of larger waves. To that end, our tasks are to exploit the knowledge of the atmospheric coupling processes by examining multiple types of MIT measurement data. The final outcome will help to enhance the predictive capability of empirical and physics-based models through interrelating and exploring dependencies of variability between essential geodetic variables.


The primary goal of JSG4 is to enhance our understanding of the interactions between solar wind and Earth, including the coupling processes within the MIT system and waves from the lower atmosphere. The study of these processes can be achieved through model simulations of the Earth’s upper atmosphere under various solar wind conditions.

  • Solar Wind Simulations: Conducting comprehensive simulations of solar wind to understand its characteristics and variability.
  • Earth Coupling Studies: Investigating the effects of solar wind on Earth’s upper atmosphere and evaluate the importance of coupled processes in the MIT system based on physical laws and principles such as continuity, energy and momentum equations and solving partial differential equations. This includes studying the coupling processes within the MIT system, associated with diurnal, seasonal, and solar wind drivers, as well as the lower atmosphere forcing. In addition, waves propagating from the Earth’s surface related to natural and anthropogenic hazards will be investigated.
  • Predictive Modelling: Developing predictive models to forecast the effects of solar wind on Earth’s upper atmosphere. This includes to determine and understand the mechanisms responsible for discrepancies between observables and predictions by present models, and explore parametrizing the effect of this mechanism. This will help in mitigating the potential detrimental effects on human technologies that depend on these models.
  • Data Sharing: Creating a web platform for sharing data and model products that are freely available for the scientific community. This will foster collaboration, accelerate research in this field, and help to achieve the above objectives.
  • International Cooperation and Scientific Dissemination: Enhancing international cooperation by sharing knowledge and research tools, organizing workshops and sessions at international conferences, co-supervising students, and helping to improve manuscripts and projects.


Selected activities aim to investigate severe geomagnetic storms during the Solar Cycle 25 to evaluate the following aspects:

  • Electrodynamics at High Latitudes: The interaction of the solar wind with the Earth’s magnetosphere has a significant impact on the high-latitude ionosphere. The Joule heating (JH), Field Aligned Currents (FACs), and electric and magnetic potentials at polar caps are utilized to evaluate the high latitude ionosphere’s response to solar wind during several case studies.
  • Magnetosphere-Ionosphere Coupling: The high-latitude ionosphere electrodynamics have a substantial impact on the low-latitude ionosphere via global ionospheric and magnetospheric coupling. FACs that flow along magnetic field lines connect the magnetosphere and ionosphere. Additionally, the JH, which is primarily found at high latitudes, can extend to low latitudes via various coupling mechanisms and have a substantial impact on the low-latitude ionosphere and thermosphere. These consequences include changes in thermospheric circulation and winds, the formation of TIDs, the regulation of equatorial electrodynamics, ionospheric storms, and plasma redistribution. An empirical model is used to investigate storm-time fluctuations in ionospheric electric potential, magnetic potential, FACs, and JH.
  • Low-Latitude Ionosphere: We plan to investigate the effects of geomagnetic storms on the low-latitude ionosphere using mechanisms such as PPEFs, disturbance dynamo effects, and thermospheric heating, which cause changes in ionospheric currents, TEC variations, changes to the EIA, and the generation or suppression of plasma irregularities.

List of Publications

Adhikari, B, V Klausner, CMN Candido, P Poudel, HM Gimenes, A Siwal, SP Gautam, A Calabia and M Shah (2024) “Lithosphere–atmosphere–ionosphere coupling during the September 2015 Coquimbo earthquake”, J Earth Syst Sci, 133, 35. doi:10.1007/s12040-023-02222-x

Calabia, A, G Lu, OS Bolaji (2023), Editorial: Advances on upper-atmosphere characterization for geodetic space weather research and applications. Frontiers in Astronomy and Space Sciences, 10:1211582, doi:10.3389/fspas.2023.1211582

Calabia, A, N Imtiaz, D Altadill, Y Yasyukevich, A Segarra, FS Prol, B Adhikari, L del Peral, D Rodriguez Frias, and I Molina (2024), Uncovering the Drivers of Responsive Ionospheric Dynamics to Severe Space Weather Conditions: A Coordinated Multi-Instrumental Approach. J. Geophys. Res. Space Phys., doi:10.1029/2023JA031862

Liu, H, P Yang, X Ren, D Mei, X Le, X Zhang, and M Freeshah (2024), The Short-Term Prediction of Low-Latitude Ionospheric Irregularities Leveraging a Hybrid Ensemble Model, IEEE Transactions on Geoscience and Remote Sensing, vol. 62, pp. 1-15, 2024, Art no. 4100615, doi: 10.1109/TGRS.2023.3346449

Freeshah, M, A Adil, E Şentürk, X Zhang, X Ren, H Liu, and N Osama (2024), A Cyclone Formation, Eastward Plume Drag, Ion-hydration Process, and the Consequent Ionospheric Changes Following the 2022 Hunga Tong-Hunga Ha’apai Volcanic Eruption. Advances in Space Research, 73(5):2457-2470, doi: 10.1016/j.asr.2023.12.029

Freeshah, M, E Şentürk, X Zhang, H Livaoğlu, X Ren, and N Osama (2024), Investigating Multiple Ionospheric Disturbances Associated with the 2020 August 4 Beirut Explosion by Geodetic and Seismological Data. Pure and Applied Geophysics., doi: 10.1007/s00024-023-03386-9

Demyanov, V, E Danilchuk, M Sergeeva, Y Yasyukevich (2023) An Increase of GNSS Data Time Rate and Analysis of the Carrier Phase Spectrum, Remote Sens. V. 15, 792. doi: 10.3390/rs15030792.

Idosa, C, B Adhikari, and K Shogile (2023), Features of ionospheric total electron content over high latitude regions during geomagnetic storm of November 04, 2021. Indian J Phys.  doi: 10.1007/s12648-023-02746-4

Maruyama, N, et al. (2023), On the Sources of Cold and Dense Plasma in Plasmasphere Drainage Plumes, J. Geophys. Res. Space Phys., in review.

Pandit, D, Amory-Mazaudier, C, Fleury, NP Chapagain, and B Adhikari (2023), VTEC observations of intense geomagnetic storms above Nepal: comparison with satellite data, CODE and IGSG models. Indian J Phys 97, 701–718. doi: 10.1007/s12648-022-02441-w

Shahzad, R, M Shah, M Arslan Tariq, A Calabia, A Melgarejo-Morales, P Jamjareegulgarn, Libo Liu (2023), Ionospheric-Thermospheric responses to June 2015 and August 2018 Geomagnetic Storms from Multi-Instrument Geodetic Space Weather Data. Remote Sens, 15, 2687. doi:10.3390/rs15102687

Uyanık H, E Şentürk, MH Akpınar, STA Ozcelik, M Kokum, M Freeshah, A Sengur (2023), A Multi-Input Convolutional Neural Networks Model for Earthquake Precursor Detection Based on Ionospheric Total Electron Content. Remote Sensing. 15(24):5690. doi:10.3390/rs15245690

Freeshah, M, N Osama, and X Zhang (2023), Using real GNSS data for ionospheric disturbance remote sensing associated with strong thunderstorm over Wuhan city. Acta Geod Geophys 58, 553–574, doi:10.1007/s40328-023-00423-w


More details can be seen on the website