Correlation between typhoon-related lightning activity and the maximum wind speed near the center examined by back-tracing technique

Abstract:

The previous study of the relationship between lightning activity and the maximum wind speed in typhoon/hurricane shows a strong correlation with the lag time of 1 to 2 days. However, the previous study still misses the explanation of why this correlation happen. Moreover, the quantitative correlation between the number of lightning and maximum wind speed has not been reported. Using the assumption that the lightning activity indicates the latent heat energy input from the ocean, we propose a new technique to enhance the understanding of the correlation between lightning and maximum sustainable wind speed using the back-tracing technique (BT). The 60 points on a circle of radius 100 km from the typhoon center were traced backward with the speed and opposite direction of winds using the ERA5 reanalysis data at various height levels. In this study, the lightning windows collection is the back-tracing point at the same time connected to forming a polygon area. Using this technique, the lag time between the peak of lightning activity and the maximum wind velocity of typhoons can be explained, considering the time interval needed for traveling from lightning location to the typhoon center.