Relationships between lightning flash rates over the tropics and subtropics and the vertical structures of precipitation radar reflectivity

Using 13 years of Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) observations, the precipitation features are defined by grouping contiguous raining regions over tropics and subtropics. The lightning flash rate in each precipitation feature is estimated by counting the number of flashes within the feature observed by TRMM Lightning Sensor. The relationships are investigated between lightning flash rates and the echo tops and the area vertical profiles of 20, 30, and 40 dBZ over 4x4 degree grids in 36S-36N. Consistent with the earlier studies, the systems over land have more flashes and with higher probabilities with flashes than those ocean given the same convective intensity proxies from radar. Comparing to the depth of the system, the areas of large radar reflectivity greater than 30 dBZ are better correlated with the lightning flash rates. This indicates that it is not the maximum strength of the storm determining the flash rates, It is the total amount of large ice particles passing through the mixed phase region that better correlate to the flash rates. The variations of relationships between the flash rates and the properties of radar profiles are shown over different regions.