Investigation of multiple cloud-to-earth lightning discharges, their development, properties and infl uence on hazard for people and objects

aim of project
The aim of the project is to determine electrical characteristics of multiple cloud-to-ground lightning discharges and electrical charge structure in the zone of their initialization in thunderstorm clouds. This requires the creation of a new local lightning detection system, which will enable to record simultaneously changes of electrical fi eld density generated by cloudto- ground discharges and observation of lightning discharges development using high speed digital cameras. The system will enable 3D location of electrical charges and estimation of the value of the charge, which is discharged in subsequent steps of multiple lightning fl ashes: fi rst stroke, subsequent strokes and long duration current. It will be possible to distinguish diff erent types of lightning discharges, i.e. uni-polar and bipolar. It is scheduled to design and install a local lightning detection network in the area of Warsaw, which will consist of six electric fi eld antennas, synchronized by GPS and equipped with digital recorders. Also, two digital fast speed cameras will be used for recording lightning discharge development in fi xed sectors of the horizon. Lightning location data and electric charge of individual cloud-to-ground discharges will be calculated using self-developed software based on electrostatic charge source model over conductive plane.

expected results
So far no research centre in Poland investigated the quality of lightning data recorded by lightning detection PERUN (SAFIR) operated by IMGW (the Institute of Meteorology and Water Management). Data of electric charge location in thunderstorm cloud discharged by multiple lightning cloud-toground fl ashes enable to discriminate the areas of multiple lightning fl ashes initialization on meteorological radar screen, which can be used for warning procedures related to hazard for people and objects. The results will also be used to verify procedures of multiple lightning fl ashes discrimination applied in 2D location in the PERUN (SAFIR) system.