Diurnal and Monthly Variability of Lightning Observation Over West Africa

Abstract

This study examines in detail lightning activities over West Africa using the worldwide lightning location network (WWLLN). The Worldwide Lightning Location Network (WWLLN; operated by the University of Washington) is a developing, experimental lightning detection network increasingly used for applications. In West Africa, there are many studies on the diurnal process of lightning activity at the regional level, but there is a shortage of literature examining the diurnal variation of lightning observation in this region. Therefore the main objective of the study is to examine the lightning activities over West Africa by presenting an evaluation of the WWLLN data as ground truth to improve the knowledge of ground-based lightning location system. For this study, the diurnal variability of flash counts (frequency) was measured over West Africa for the three climatic sub-region (Guinea, Savannah and Sahel) sub-regions using a line graph to plot the flash counts (frequency) over time. All regions exhibit a strong diurnal variation, with lightning activity peaking in the late afternoon between 1500 and 1700 WAT and decreased in the late morning between 0900 and 1100 WAT. The diurnal amplitude varies by location throughout West Africa.