On the influence of elevated strike objects on directly measured and indirectly estimated lightning currents

The knowledge of lightning current parameters comes essentially from direct measurements obtained using instrumented towers or triggered lightning, and from measurements of lightning electromagnetic fields assuming empirical or theoretical relations between fields and currents (indirect estimation). In this paper, the effects of an elevated strike object on both the direct and indirect estimation of the current parameters is examined. It is shown that relatively short strike objects, such as triggered lightning launching structures, may not appreciably affect the calculated field peak values and overall wave shapes, but could affect the field derivatives.