Climatology of lightning activity in Australia: spatial and seasonal variability

Abstract

A climatology of lightning ground flash density is examined for the Australian region based on 18 years of data. The dataset and methodology used are consistent with that of a previous study based on eight years of data. Lightning flash densities are obtained from two satellite instruments—the Lightning Imaging Sensor and the Optical Transient Detector. A climatological map of lightning ground flash density is produced, covering the Australian region, representing the most comprehensive map of its type to date. For the first time, we present (i) maps detailing the seasonal variability of the lightning ground flash densities and (ii) examinations for the maritime regions surrounding the Australian continent as well as for land regions. A notable feature of the climatology is that a maximum in lightning activity during the cooler months occurs over the ocean to the east of the continent. The period of data available for this study is over twice as long as for the previous study, thereby allowing a significant update to the climatology. Results of this study are intended for use in relation to hazards associated with lightning occurrence and applications such as lightning safety standards.