Additional flight delays and magnetospheric–ionospheric disturbances during solar storms

Abstract

Although the sun is really far away from us, some solar activities could still influence the performance and reliability of space-borne and ground-based technological systems on Earth. Those time-varying conditions in space caused by the sun are also called solar storm or space weather. It is known that aviation activities can be affected during solar storms, but the exact effects of space weather on aviation are still unclear. Especially how the flight delays, the top topic concerned by most people, will be affected by space weather has never been thoroughly researched. By analyzing huge amount of flight data (~ 4 × 106 records), for the first time, we quantitatively investigate the flight delays during space weather events. It is found that compared to the quiet periods, the average arrival delay time and 30-min delay rate during space weather events are significantly increased by 81.34% and 21.45% respectively. The evident negative correlation between the yearly flight regularity rate and the yearly mean total sunspot number during 22 years also confirms such correlation. Further studies show that the flight delay time and delay rate will monotonically increase with the geomagnetic field fluctuations and ionospheric disturbances. These results indicate that the interferences in communication and navigation during space weather events may be the most probable reason accounting for the increased flight delays. The above analyses expand the traditional field of space weather research and could also provide us with brand new views for improving the flight delay predications.

Characteristics of flight delays during solar flares

“…The average delay time during solar X-ray events is 44.75 min (median: 25 min), which is 7.67 min (median: 5 min) longer than during quiet periods. These findings demonstrate that flight departure delays will increase during solar X-ray events, consistent with our previous study on arrival delays 21 . The longitudinal effect (local time) is a key factor that affects the Earth's response to solar flares 33 .…”

“…It has been previously demonstrated that there exists a linear correlation between the arrival delay and departure delay 27,28 . In addition, our previous study 21 has examined the effect of space weather on arrival delays, which can be contrasted with the present work. Thus, the focus of the current analysis is on the departure delay rather than the arrival delay.…”

“…Although we have removed the influence of additional major space weather events, such as coronal mass ejections and solar proton events, there may still be some measurable solar effects that could contaminate the "quiet periods" in our analyses. However, these "contaminations" can only underestimate the impact of solar flares on flight delays 21 , which does not change the overall conclusions. Besides, to ensure that there are indeed differences in flight delays, we conducted the two-sample Kolmogorov-Smirnov test on the "quiet periods" and various "solar X-ray event periods" shown in Figs.…”

“…To eliminate the influence of accidents, a comparative study similar to Mitsokapas et al 29 was adopted, but with a larger research sample size (~ 5 × 10 6 records over 5 years). It is worth noting that the selected solar X-ray events were randomly distributed across weekdays and months, thereby minimizing the influence of weekday and season effects on the results 21 . Nevertheless, the fact that flight delays exhibit a 24-h intrinsic period is one of the most important factors considered in this study 21 .…”

“…It is worth noting that the selected solar X-ray events were randomly distributed across weekdays and months, thereby minimizing the influence of weekday and season effects on the results 21 . Nevertheless, the fact that flight delays exhibit a 24-h intrinsic period is one of the most important factors considered in this study 21 . The "24-h intrinsic period" is that flight delays vary significantly at different moments of the day [30][31][32] .…”