A preliminary study of thunderstorm tracking based on single-station observations of NBEs

Abstract:

Based on an developed three-dimensional (3D) location method of narrow bipolar events (NBEs) with single-station measurement of low-frequency (LF) magnetic fields, we examined two typical thunderstorms (on August 17, 2013 and August 17, 2013, respectively) in North China and obtained the location of 700 and 387 NBEs. The results were evaluated by comparing with radar observations, showing that NBEs occurred mainly in strong echo area. NBEs located with our method are distributed between 6-18 km with a clear dividing line at about 14 km: positive NBEs (84%) occurred mainly in 6-14 km while the negative (16%) concentrated in 14-18 km, consistent with previous work based on the detection of multi-station network. The comparison of results at different stages showed that the trend of NBEs occurrence was consistent with the thunderstorm motion, and the location data averaged over 30-minute time window evidently proved the tracking capability of NBE detection for severe thunderstorms. Therefore, the NBE detection based on the single-station magnetic measurement could be used as a convenient approach for monitoring the development of convective thunderstorms, especially when they are far beyond the detection range of meteorological radars. New measurements in summer of 2015 will be examined by comparing the location result with that derived from a long-baseline network of LF magnetic sensors using the time-of-arrival technique.