Analysis of ionospheric TEC  disturbances caused by typhoon Lekima based on IGS Data

In this paper we use the global GIM grid ionosphere data provided by IGS to investigate the ionospheric TEC disturbances induced by typhoon lekima in 2019. By means of the sliding interquartile range method, the temporal and regional spatial changes of the ionospheric TEC during typhoon Lekima were analyzed. It was found that the ionospheric TEC showed positive abnormal changes on the fifth day before the typhoon. On the second day after typhoon landing, the ionospheric TEC anomaly over the typhoon affected area changes from positive anomaly to negative anomaly and then changes to positive anomaly. The maximum value of positive anomaly reaches 8 TECU, and the maximum value of negative anomaly reaches 6 TECU. The maximum abnormal point does not coincide with the eye of the wind, but appears in the southwest region of the centre. This analysis suggests that this ionospheric TEC  disturbances may be related to the change of wind speed and direction during the landing of typhoon