Indian scientists improve space weather mapping for better navigation

The research team addressed this challenge by introducing a method that calculates how the topside scale height changes with altitude instead of assuming it remains constant.

Researchers in India have developed a new technique to map the upper part of Earth's ionosphere with greater accuracy, marking the first time such a region-specific model has been created for the Indian region using both ground-based and satellite observations. The breakthrough could improve satellite operations, communication networks and navigation services by providing a clearer understanding of how signals travel through Earth's upper atmosphere.

The work was carried out by scientists at the Indian Institute of Geomagnetism (IIG), an autonomous institute under the Department of Science and Technology (DST). By combining measurements from ground-based ionosondes with space-based COSMIC radio occultation data, the researchers have produced a more realistic picture of the topside ionosphere, an area extending hundreds of kilometres above Earth where charged particles can strongly influence radio and satellite signals.

The findings have been published in the journal AGU Radio Science.

Better understanding of the ionosphere can strengthen communication systems

The ionosphere is a layer of Earth's upper atmosphere filled with electrically charged particles that affect the way radio waves and satellite signals travel. Changes in electron density from one day to another can influence high-frequency radio communication and reduce the accuracy of satellite navigation systems such as GPS and India's NavIC.

Reliable information about electron density is especially important up to an altitude of around 1,000 kilometres because many low Earth orbit satellites operate within this range. Accurate models help scientists monitor space weather conditions while allowing communication and navigation systems to perform more reliably.

Earlier ionospheric models often relied on a fixed value for the topside scale height, an important parameter used to estimate how electron density changes with altitude. Because reliable regional measurements were limited, especially over India, these simplified assumptions frequently reduced the accuracy of existing models.

New approach offers more accurate regional space weather predictions

The research team addressed this challenge by introducing a method that calculates how the topside scale height changes with altitude instead of assuming it remains constant. The model combines observations from COSMIC radio occultation satellites with bottomside ionosonde measurements, producing a more realistic electron density profile over the Indian region.

The approach is particularly valuable near the geomagnetic equator, where Earth's magnetic field creates highly complex ionospheric behaviour that is difficult to represent using conventional models.

The study, conducted by K. Siba Kiran Guru, S. Sripathi and R. K. Barad, demonstrated that the new reconstruction technique closely matched independent satellite observations, confirming its accuracy. Researchers believe the method can also be adapted for other parts of the world, improving regional ionospheric models under different space weather conditions.

The improved understanding of the topside ionosphere is expected to strengthen space weather forecasting while supporting more reliable satellite communication, navigation systems and future space missions. As dependence on satellite-based technologies continues to grow, advances such as this will play an increasingly important role in ensuring stable communication and positioning services for both civilian and scientific applications.