The impact of cloud microphysics on thunderstorms electrification

Abstract

Lightning are electrical atmospheric phenomena with important consequences for society. In Brazil, for example, due to its large land area, it is estimated that 50 million lightning strike annually causing dozens of deaths and losses of a billion dollars to society. Several studies of lightning have the common observation that hydrometeors within clouds are crucial for lightning formation and occurrence. Therefore understanding how clouds become electrified and what the role of microphysics in the processes of lightning can promote more accurate tools to lightning nowcasting, such as help in mitigating its effects on society. In this context, the main objective of this project is to determine the impact of clouds microphysical on electrification and characteristics of lightning. Polarimetric radar measurements and observations of lightning in two and three dimensions and speed camera recording are will combined for study thunderstorms between November and December 2011 on the region comprising the cities of Sao Jose dos Campos and Sao Paulo. The methodology will be addressed in three steps: (I) assessment of how different types of hydrometeors modulate the structure and electrical characteristics of lightning during the thunderstorms life cycle, (II) establishment of the regions most favorable for formation and propagation of electrical discharges within the clouds, and (III) determining the impact of the electrical charge center physical properties on the cloud-to-ground lightning physical processes. This project will be inserted in the CHUVA project scope within of the subproject called Eletrification Process: Moving from Clouds to Thunderstorm. (AU)