Relationship between lightning and cloud microphysics in the Northeast of Brazil
Remote sensing, lightning, TRMM, LIS, thunderclouds
In the history of mankind, lightning has been the focus of scientific observation in many research groups around the world, mainly because of its aggressive and destructive nature. Theseimportant atmospheric phenomena can greatly impact the society, leading to abnormalities or disconnections in power distribution, fires, ship and airplane accidents, telecommunication breakdowns and even death. It is estimated that about 60-75 million lightning occur annually, killingan average of 132 people every year in Brazil. The Northeast region of Brazil (NEB) accounts for 18% of the total deaths in the national territory. Considering the population of all Brazilian regions, the state of Piauí presented the highest mortality rate (1.8); which is higher than the country’s total rate (0.8) and the NEB rate (0.5). Studies have shown that lightning formation is associated with the collision between ice particles (crystal and graupel) in the presence of supercooled water droplets in regions with strong updraft. Therefore, the objective of this study is to evaluate lightning spatial and temporal distribution in the Northeast region of Brazil, as well as to investigate the relationship between lightning and cloud microphysics, during the period from 1998 to 2013. Data from three orbital sensors will be used: i) Lightning Imaging Sensor (LIS) and TRMM Microwave Imager (TMI) from the Tropical Rainfall Measuring Mission (TRMM) satellite to provide information on the occurrence of lightning and ice water path, respectively; ii) Operational Land Imager (OLI) from the Landsat platform to provide land use and soil occupation data, in order toidentify urban agglomerations near areas with high lightning density; and iii) ground elevation data from the Terra platform (Advanced Spaceborne Thermal Emission and Reflection Radiometer – ASTER) to verify the influence of topography on lightning rates. Data will be worked in monthly, seasonal and total climatology formats. Principal Component and Cluster Analysis of monthly data will be carried out, while total climatology analysis will help to identify lightning hotspots. Finally, lightning will be analyzed according to the quantile technique, where each of the tertiles will be characterized according to the microphysical characteristics of clouds.