Study finds strikes disrupt satellite signals; causes possible GPS errors — here's how

BENGALURU: Lightning does much than airy up the entity and shingle the ground. A caller India-wide survey shows that almighty lightning strikes tin concisely disturb the ionosphere, the electrically charged furniture of the ambiance important for outer navigation and vigor communication.The research, published successful Remote Sensing Letters, combines information from Isro’s Lightning Detection Sensor Network with GPS measurements from aggregate stations — Bengaluru, Hyderabad, Lucknow and Kanpur — crossed India.The squad tracked however cloud-to-ground lightning during March and April 2024 affected full electron contented (TEC), a cardinal parameter that determines however vigor signals question done the ionosphere.

TEC represents the fig of escaped electrons on the way betwixt a outer and a crushed receiver.Changes successful TEC tin distort signals utilized by GPS, NavIC and different satellite-based systems. While star enactment and geomagnetic storms are known to origin large-scale TEC disturbances, the relation of lightning has remained poorly understood.The applicable implications prevarication successful navigation and connection systems that beryllium connected precise awesome timing.

“Whatever connection we get, GPS signals, adjacent trans-ionospheric communications, person to transverse done the ionosphere. So electron density changes volition interaction everything,” Alok Taori, a idiosyncratic astatine Isro’s National Remote Sensing Centre (NRSC), and the pb writer of the study, told TOI.India experiences immoderate of the world’s highest lightning activity, peculiarly during the pre-monsoon and monsoon months.

While the TEC variations identified successful the survey are modest, they could lend to positioning errors erstwhile combined with different sources of ionospheric disturbance.The researchers accent that lightning is not replacing star enactment arsenic the ascendant operator of ionospheric change. Instead, it adds different furniture of short-term variability that existent correction models often ignore.“That overmuch mistake has to beryllium taken into relationship whenever you are doing positioning,” Taori said, pointing to applications ranging from civilian navigation to much delicate systems that trust connected precocious accuracy.As satellite-based services proceed to expand, the survey highlights the request to origin successful not conscionable abstraction weather, but besides what is happening acold below, wrong Earth’s astir convulsive storms.“The relation of lightning was little understood. While we knew star vigor could disturb the ionosphere, the question was, tin immoderate different vigor root bash the aforesaid during daytime?” Taori said. To isolate the effect of lightning, researchers focused connected geomagnetically quiescent days, ruling retired star and space-weather influences.They analysed lightning events crossed antithetic parts of India and compared them with minute-by-minute GPS-derived TEC information from stations successful Bengaluru, Hyderabad, Kanpur and Lucknow.What emerged was a accordant pattern. Strong lightning discharges were followed by tiny but measurable TEC fluctuations, typically wrong 2 to 35 minutes. The changes ranged from astir 0.05 to 0.8 TEC units, depending connected the strength of the lightning current.“We recovered that lightning besides creates immoderate benignant of saltation which is astir one-fifth of immoderate the Sun really does,” Taori said.The survey besides recovered a anemic but wide linear narration betwixt lightning existent spot and the size of the TEC disturbance. In elemental terms, stronger lightning flashes were much apt to nutrient larger ionospheric effects. These disturbances appeared arsenic crisp spikes superimposed connected slower atmospheric waves generated by thunderstorms.Importantly, the effects were observed during daytime, erstwhile the ionosphere is already dense and comparatively stable. Earlier studies had mostly focused connected nighttime disturbances oregon azygous lightning events. By utilizing aggregate stations and respective lightning-active days crossed India, the caller enactment provides the archetypal systematic grounds of lightning-driven TEC changes implicit the region.