Lightning detection in Southeastern Brazil from the new Brazilian Total Lightning Network (BrasilDAT)

Abstract

The Brazilian Total Lightning Network (BrasilDAT) combines advanced lightning detection technologies with modern electronics and already covers 11 States of Brazil. The network is composed of 48 EarthNetworks Lightning Sensors (ENLS), each of them with a GPS-based timing circuit, a digital signal processor (DSP) and onboard storage and internet communication equipment. The ENLS is a wideband system with detection frequency ranging from 1Hz to 12MHz. The wide frequency range enables the sensor to not only detect cloud-to-ground (CG) strokes, but also intra-cloud (IC) pulses. The sensor records whole waveforms of each event and sends them back, in compressed data packets, to the central processor. Instead of using only the peak values, the whole waveforms are used in locating the events and differentiating between IC and CG discharges. Sophisticated digital signal processing technologies are employed on the server side to ensure high-quality detections and to eliminate false locations. This paper presents some preliminary results of two severe storms in Southeastern Brazil that were tracked by BrasilDAT showing the spatial and temporal evolution of IC and CG discharges compared to radar, satellite images and numerical model products. Those results showed the potential of total lightning information for CG lightning warning purposes.