Estimates of lightning ground flash density in Australia and its relationship to thunder-days
نویسنده
چکیده
Lightning is a phenomenon that is highly variable in space and time. The derivation of reliable estimates of its activity, therefore, requires statistical averaging over a large area and a considerable number of years of observation. The lightning flash density, defined as the number of flashes of a specific type occurring on or over unit area in unit time, is widely used as a statistical description of lightning activity. This parameter is commonly expressed as a number of flashes per square kilometer per year (km-2 yr-1). Of greater interest for lightning protection purposes is the lightning ground flash density Ng – the number of flashes striking a unit area of the ground per unit time, preferably Aust. Met. Mag. 53 (2004) 189-196
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