Engineering of high voltage discharges

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As we admire from afar the spectacular display of nature's temper provided by the lightning, we cannot hide the fear it instils.  And our instincts are right.  A lightning strike has the potential of causing irreparable damage to everything it touches and on occasion it leads to loss of life.  Even at a distance, electromagnetic radiation from the lightning path may induce sufficient voltage to be responsible for permanent loss or at least for temporary malfunction of electrical apparatus and electronic components.         While protection efforts against detrimental effects of direct lightning strikes date as far back as Benjamin Franklin, through experimental observations pertinent knowledge about the danger of indirect strikes is gained with every new day.  Advances in the miniaturization of electronic components make our instrumentation much more handy yet also more susceptible to the incident electromagnetic field.  For that reason requirements on details about the technical characteristics of a lightning event are continuously becoming more and more stringent.  Fortunately improved instrumentation can provide the needed more precise information.       The requested support for the Discovery Grant will be used to pursue studies at the CN Tower on three aspects of the lightning phenomenon: (1) To perform simultaneous measurements of the lightning current within the CN Tower and of the electromagnetic radiation it emanates.  Appropriate visual aspects of the lightning flash will also be recorded.  (2) To develop computational models that could help to establish the relation between the current within the lightning path and the resultant electromagnetic field incident at a specified geographic location.  For their verification these models will be compared to measured results collected under item 1.  (3) To engage in studies of other aspects of lightning, such as the distribution of lightning current within the CN Tower and within ground in its vicinity.       Results of proposed investigations will provide needed information for use in standards and regulations on lightning protection and thereby safeguard structures, avoid accidents at airports and hopefully save lives.