Clouds’ Microphysical Properties and Their Relationship with Lightning Activity in Northeast Brazil

Lizandro Pereira De Abreu,Pedro Rodrigues Mutti,Weber Andrade Gonçalves,Daniele Torres Rodrigues,Marcos Paulo Araújo Da Silva,Enrique Vieira Mattos

doi:10.3390/rs13214491

Abstract

The Northeast region of Brazil (NEB) has a high rate of deaths from lightning strikes (18% of the country’s total). The region has states, such as Piauí, with high mortality rates (1.8 deaths per million), much higher than the national rate (0.8) and the NEB rate (0.5). In this sense, the present work analyzes the microphysical characteristics of clouds with and without the occurrence of total lightning. For this purpose, data from the Lightning Imaging Sensor (LIS), TRMM Microwave Imager (TMI) and Precipitation Radar (PR), aboard the Tropical Rainfall Measuring Mission (TRMM) satellite from 1998 to 2013 were used. The TRMM data were analyzed to establish a relationship between the occurrence of lightning and the clouds’ microphysical characteristics, comparing them as a function of lightning occurrence classes, spatial location and atmospheric profiles. A higher lightning occurrence is associated with higher values of ice water path (>38.9 kg m−2), rain water path (>2 kg m−2), convective precipitation (>5 mm h−1) and surface precipitation (>7 mm h−1), in addition to slightly higher freezing level height values. Reflectivity observations (>36 dBZ) demonstrated typical convective profile curves, with higher values associated with classes with higher lightning densities (class with more than 6.8 flash km−2 year−1).

Highlights

Northeast Brazil (NEB) is a predominantly semiarid region, where society and agricultural productivity can be significantly impacted by climate variability [1,2,3]
The means of the two distributions were compared as a function of the Student t-test results, and at 99% confidence, it was possible to state that the means of the two distributions are different
This study evaluated, in pioneering fashion, the behavior of microphysical properties as a function of occurrence and non-occurrence of lightning in the Northeast region of Brazil, as well as the spatial distribution of these characteristics in the region

Summary

Introduction

Northeast Brazil (NEB) is a predominantly semiarid region, where society and agricultural productivity can be significantly impacted by climate variability [1,2,3]. Meteorological systems that cause intense precipitation are extremely important to fill reservoirs that provide water during the dry period [4,5]. Some of these systems, especially those composed of clouds with extensive vertical development, high amounts of ice and strong updrafts, have the potential to produce electrical charges inside the clouds and, lightning [6,7,8]. Several papers were published deepening knowledge about the relationship between lightning and the characteristics of precipitation systems, in different locations around the globe, such as China [16], Bangladesh [17], Kolkata-India [18], France [19] and Brazil [7,20,21]. Some studies have indicated that the relationship between precipitation regime and lightning is highly dependent, a more robust relationship can be found between lightning and microphysics [22]

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