GLOBAL LIGHTNING ACTIVITIES AND THEIR REGIONAL DIFFERENCES OBSERVED FROM THE SATELLITE
卫星观测到的全球闪电活动及其地域差异

The lightning activity changes greatly in temporal and spatial scales. We use the data from the lightning imaging sensor, boarded on the Tropical Rainfall Measurement Mission (TRMM) satellite, to study the lightning activities in several typical regions in the world. It is found that great differences exist in various regions for both the flash rate and flash intensity. The flash rate on the ocean is tens to hundred times smaller than that on the continent. The number difference of lightning activities in different regions is caused by not only the thunderstorm number but also the flash rate in an individual thunderstorm. The discharge intensity shows a decreasing tendency with the increase of flash number in different regions. Further studies show that the difference of flash optical radiance between different regions can be interpreted by the local Convective Available Potential Energy (E CAPE ). The optical radiance is linearly related to the E CAPE value for different regions, but no obviously correlation is found between the flash frequency and the E CAPE value.