An initial assessment of the distribution of total Flash Rate Density (FRD) in Brazil from GOES-16 Geostationary Lightning Mapper (GLM) observations

Abstract

Brazil is one of the regions in the world where lightning most occurs. With the launch of the Geostationary Environmental Operational Satellite – 16 (GOES-16), it was possible, for the first time, to carry out an almost uniform resolution mapping, in near real time, of total lightning with a field of view that covers most of the western hemisphere. The objective of this study was to evaluate the initial spatio-temporal distribution of the Total Lightning Flash Rate Density (FRD) for all of Brazil, and to determine lightning hotspots in cities in five regions, the South, the Southeast, the Midwest, the Northeast, and the North. Total lightning flash data from the Geostationary Lightning Mapper (GLM) sensor on board the GOES-16 were evaluated for a three-years period (from 2018 to 2020). The greatest FRD (about 30 fl km−2 season−1) occurred during the hot season (between spring and summer), mostly in the late afternoon (12–18 Local Hour, LH), in the northwest-southeastern portion of the country (AM, PA, MT, GO and TO), in the southeastern of RJ and closer to the Brazil-Argentina border (MS, PR, SC and RS). The lowest FRD values were observed along coastal regions, extending from the north of RJ to AP, and for the north of RO and PA. São Félix do Xingu city in Pará came in first (131 fl km−2 year−1) in the national ranking for lightning hotspots, showing well-defined monthly and daytime cycles with maximums at 14 LH.