Lightning Characteristics of Tropical Storm Bebinca (2013) and Super Typhoon Rammasun (2014)

The World Wide Lightning Location Network (WWLLN) data was used to analyze the lightning activities of Tropical Storm Bebinca (2013) and Super Typhoon Rammasun (2014). The relationships between lightning activity and cyclonic intensity change, direction of storm motion of the two tropical cyclones were also investigated. Preliminary analyses showed that the two systems produced a large number of lightning strokes in the region of
$0\sim800\ km$
from the centers, the numbers are 111,289 and 125,046 for Bebinca and Rammasun, and the average lightning stroke rate of Bebinca was 1021 str/h and that of Rammasun was 680 str/h. Both for Bebinca and Rammasun, their lightning frequency were oscillating in the whole lives, however, it was varied little for Rammasun and decreased for Bebinca. The radial and spatial distribution of lightning showed that the lightning of Bebinca mainly appeared at rain band outside of 300 km and most of lightning occurred at the west of cyclone. For Rammasun, lightning mainly produced in the regions of 160 km away from center, including the inner rainband and outer rainband, and mainly centralized in the west of cyclone. When the area around each storm was divided into four quadrants with respect to storm motion, right and left front, and right and left rear, the maximum number of flashes occurred in the left-rear quadrant of Bebinca, while in the right-front and left-front quadrant of Rammasun. The relationship between lightning frequency and intensity change for Bebinca was weak, while strong for Rammasun. The moving directions of Bebinca and Rammasun exhibited a weak relationship with lightning frequency, but well correlated with lightning spatial distribution.