A climatology of atmospheric pressure jumps over southeastern Australia

Abstract

Black Saturday provided the first evidence of an atmospheric bore affecting the behaviour of a bushfire. As the bore passed, the fire unexpectedly strengthened. This behaviour highlighted the lack of understanding of how common bores are in the southeastern part of Australia, a region of relatively high bushfire risk. The present study addresses that lack of understanding. Pressure jumps are identified in the 1 min records at four automatic weather stations in southeastern Australia by correlating the pressure time series with a large-amplitude step function. These jumps are then separated into two classes: bores and frontal pressure jumps. Bores are defined as pressure jumps without a chang..