Topside Ionospheric Reconstruction

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Why in News?

Recently, researchers have developed a novel approach to reconstruct the topside ionosphere over the Indian region.

Ionosphere – Ionized part of Earth’s upper atmosphere (60–1000 km).
It influences radio wave propagation, high frequency communication, GPS and NAVIC signals of LEO satellites.
Low Earth Orbit (LEO) Satellites – They operate between 160 km – 2,000 km above the Earth and it requires accurate electron density data.

Importance of Electron Density Data

Assumption – Conventional models assume constant topside scale height.
Uneven electron density – Near the geomagnetic equator (India’s region), electron density changes unevenly due to complex magnetic field and solar effects.
Result – Using a constant value miscalculates signals, leading to GPS, NAVIC, and satellite errors.

Topside (400–1000 km) is the ionosphere’s upper region; scale height shows how fast electron density thins with altitude.

New Methodology – Topside ionospheric reconstruction method

Developed by – Indian Institute of Geomagnetism (IIG) and Department of Science and Technology (DST)
Integration – Combines data from COSMIC radio occultation data (altitudinal scale height variation) with ionosonde bottom-side profiles.
Output – More realistic electron density profiles up to 1000 km.
Validation – Correlation with the Swarm satellite in‑situ electron density confirms robustness.
Result – Provides region‑specific estimates of topside scale height gradient, especially over the geomagnetic equator.
Significance – Improves reliability of communication, navigation, and remote sensing.
Supports India’s satellite programmes, GPS/NAVIC accuracy, defence communication and space weather prediction

Reference

PIB | Topside Ionosphere