High resolution lightning density maps to study elevation effects at microscale

Abstract

Lightning location systems have evolved over the years in both location accuracy and detection efficiency. For the Brazilian integrated lightning detection network (RINDAT), the mean location accuracy has increased along the years as the network was expanded and the performance and sensibility were being improved. With the improved location accuracy, accurate and reliable high-resolution lightning distribution maps may be obtained. These maps might then be used to give a better understanding of the lightning distribution and its physical basis. In this paper we analyze the terrain effects in a microscale perspective, using eleven years (1999 to 2009) of data from the RINDAT network to produce the high-resolution maps. These maps are accomplished by a thunderstorm initiation analysis based on the lightning data. The results indicate some interesting elevation effects on the lightning distribution, especially over (isolated) mountains near Sao Paulo and Belo Horizonte and along the coastline of Sao Paulo, which might be related to local storms thermodynamic and/or channel attachment processes.