New Research Uncovers Hidden Ionospheric Causes of GNSS Positioning Errors in Asia

KNOXVILLE, TN, April 03, 2026 -- A new study in *Satellite Navigation* reveals that satellite positioning accuracy can be compromised not only by dramatic space weather but also by localized, sharp ionospheric structures. Led by the Institute of Geology and Geophysics, Chinese Academy of Sciences, this research focuses on the Asian sector, identifying specific regional ionospheric conditions that cause significant Global Navigation Satellite System (GNSS) errors. This understanding is crucial for improving global navigation system reliability.

The study pinpoints two primary culprits: steep longitudinal gradients in Total Electron Content (TEC) and storm-time ionospheric irregularities. Using data from over 300 GNSS receivers across Asia, researchers found TEC gradients exceeding 2 TECU per degree, which standard global ionosphere models often fail to resolve. Critically, storm-time electric fields were shown to either amplify precise positioning errors or, surprisingly, reduce them by suppressing irregularities, challenging the notion that all space weather is uniformly detrimental.

These findings offer significant operational value. GNSS users in Asia—from surveying to autonomous technologies—could benefit from advanced warning systems tracking not just storm intensity, but also steep TEC gradients and storm-time electric field direction. The research advocates for practical model improvements, including finer longitudinal resolution and more realistic multi-layer ionosphere representations, promising more accurate and actionable GNSS forecasting. DOI: 10.1186/s43020-026-00191-2