IIG method reconstructs the topside ionosphere over India for the first time
Researchers at the Indian Institute of Geomagnetism developed a method to reconstruct the topside ionosphere over the Indian region by combining COSMIC radio occultation data with ground ionosonde observations (DST release, 8 July 2026).
Summary
The Indian Institute of Geomagnetism (IIG), an autonomous institute of the Department of Science and Technology, has developed a method to reconstruct the topside ionosphere over the Indian region for the first time, as reported by DST on 8 July 2026. Instead of assuming a constant topside scale height, the method combines the altitude-wise variation of scale height derived from COSMIC radio occultation measurements with bottomside ionosonde observations to get more realistic electron density profiles, validated with Swarm satellite data over Tirunelveli. Accurate electron density up to about 1,000 km matters because most low Earth orbit satellites operate in this range and the ionosphere affects HF radio and navigation systems such as GPS and NavIC. The study by K Siba Kiran Guru, S Sripathi and R K Barad appears in the AGU journal Radio Science.
Key facts
- Institute
- Indian Institute of Geomagnetism (DST autonomous institute)
- Data combined
- COSMIC radio occultation + ground ionosonde; validated with Swarm
- Station shown
- Tirunelveli
- Why it matters
- LEO satellites, HF radio, GPS/NavIC navigation
- Journal
- Radio Science (AGU)
- Authors
- K Siba Kiran Guru, S Sripathi, R K Barad
Practice MCQs 1 questions
To reconstruct the topside ionosphere over India, IIG researchers combined bottomside ionosonde observations with scale-height data from which source?
Show answer
Correct answer: B — COSMIC radio occultation measurements
The method combines altitude-wise scale height derived from COSMIC radio occultation measurements with bottomside ionosonde observations.